Record birthday control delivery PR (#67)

docs/ux/exchange-workspace.md

@@ -302,33 +302,6 @@ that contradicts displayed balances or usage without explaining the fixtures.
 - Keep unrelated accounts/history accessible during a pending operation. Do not
   block the whole product behind an exchange spinner.
 
-## Empty currency accounts (task #66)
-
-The shared empty-account message used on Accounts and transfer screens explains
-that no currency accounts have been set up and directs the customer to support
-to request setup. English and Russian no longer suggest that refreshing creates
-accounts or imply that automatic provisioning is underway. This follows the
-existing support guidance for missing funding and payout setup. The application
-has no configured support contact channel; the message therefore provides text
-guidance without a nonfunctional contact button or invented contact details.
-
-UX review: the copy names the missing resource and the next step, retains the
-existing wrapping text and accessible reading order, and does not alter loading,
-error or populated-state behavior. Existing manual refresh remains available for
-accounts provisioned externally. This copy-only change adds no controls or
-journey outcomes and requires no new analytics events. Existing transaction
-journey signals and their production measurement limitations below still apply;
-support resolution and external account provisioning are not measured in-app.
-
-Validation: `flutter gen-l10n`, `flutter analyze` in `frontend/app`,
-`make test-frontend` (217 tests), and `git diff --check` passed. No Dart source
-changed, so Dart formatting was not applicable. Existing responsive workspace
-tests cover Russian at 320px with enlarged text; this copy-only change does not
-add a dedicated empty-state rendering or native screen-reader test. No security
-scan was requested. Delivery: [task #66](https://git.sendico.io/tech/sxchnge/issues/66),
-branch `wallet-66`, [PR #68](https://git.sendico.io/tech/sxchnge/pulls/68).
-Merge and deployment remain separate.
-
 ## Journey measurement plan
 
 Reuse the typed analytics abstraction and maintain a separate journey per active

docs/ux/kyc.md

@@ -211,3 +211,51 @@ smoke testing on the local demo opened the selector, searched for Poland and
 confirmed that the profile displays Poland after selection. Focused and full
 journey tests verify the stored `PL` code. Generated localization/build outputs
 remain ignored and uncommitted.
+
+## Birthday entry — task #67
+
+Task [#67](https://git.sendico.io/tech/sxchnge/issues/67), branch `kyc-67`.
+Delivery: [PR #70](https://git.sendico.io/tech/sxchnge/pulls/70).
+This change is stacked on the residence-country selector in PR #65; merge #65
+before the birthday PR.
+
+The profile uses labeled Day, Month and Year controls. Day and year accept numeric
+entry with birthday autofill hints; month selection uses localized month names
+and standard Material keyboard/touch interaction. Customers can enter their birth
+year directly. No calendar paging or transport-format punctuation is required.
+The controls share a row when space allows and stack at narrow widths or enlarged
+text sizes. English and Russian labels, month names and errors follow the app locale.
+
+Valid calendar dates are normalized to the existing `IdentityProfile.dateOfBirth`
+`YYYY-MM-DD` value through `IdentityProvider.updateProfile`. Partial, impossible
+and future dates clear that profile value so Continue cannot retain an earlier
+valid birthday. Local input components remain visible while correcting a date;
+complete invalid dates receive a specific live-region error below the group.
+Leap years, zero day/year and calendar rollover are checked. Today's date follows
+the existing model policy; no minimum age or arbitrary oldest birth year is added.
+Prefilled dates, locale changes and external profile replacement synchronize the
+controls. Back navigation restores the valid saved date. Busy state disables all
+three controls. Controllers are disposed with the widget.
+
+The existing DTO, mapper, service, domain model and provider boundaries are retained.
+No dependency, transport or backend change is needed. This remains part of the KYC
+preparation-to-submission journey defined above: existing acceptance, failure,
+retry and abandonment signals apply, without new field events or date collection.
+The existing server-side review measurement gaps remain unchanged.
+
+UX review and automated checks cover entry/correction, leap dates, invalid and
+future-date recovery, numeric restrictions, prefill/replacement/clearing, locale
+switching, disabled state, Tab/Enter/arrow-key month selection, Escape cancellation,
+and Russian controls/errors at 320px with 1.6 text scale. Labeled and minimum-size
+tap-target guidelines pass. Integration checks verify that invalid dates block
+Continue, Back preserves the birthday, and EN/RU flows still reach submission
+acceptance. Native screen-reader and mobile keyboard/autofill testing remain
+release checks; widget semantics are not a claim of device-level validation.
+
+Validation: all four changed Dart files pass the format check; `flutter analyze`
+in `frontend/app` reports no issues; `make test-frontend` passes all 230 tests,
+including the seven new birthday widget tests and the new navigation/gating test.
+`flutter build web` passes, including its Wasm compatibility dry run. Browser
+smoke testing of the release build entered 23 April 1990, verified the inline
+error for 31 April and restored 23 April without losing month or year.
+Generated localization and build outputs remain ignored and uncommitted.

frontend/app/lib/kyc/birth.dart

@@ -0,0 +1,206 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+import 'package:intl/intl.dart';
+
+import '../generated/i18n/app_localizations.dart';
+
+/// Birthday entry with a canonical date string at the profile boundary.
+class BirthField extends StatefulWidget {
+  const BirthField({
+    super.key,
+    required this.value,
+    required this.onChanged,
+    this.enabled = true,
+  });
+
+  final String value;
+  final ValueChanged<String> onChanged;
+  final bool enabled;
+
+  @override
+  State<BirthField> createState() => _BirthFieldState();
+}
+
+class _BirthFieldState extends State<BirthField> {
+  final _day = TextEditingController();
+  final _year = TextEditingController();
+  final _monthField = GlobalKey<FormFieldState<int>>();
+  int? _month;
+  late String _emitted;
+
+  @override
+  void initState() {
+    super.initState();
+    _readValue();
+  }
+
+  @override
+  void didUpdateWidget(BirthField oldWidget) {
+    super.didUpdateWidget(oldWidget);
+    if (widget.value != _emitted) {
+      _readValue();
+      _monthField.currentState?.didChange(_month);
+    }
+  }
+
+  void _readValue() {
+    _emitted = widget.value;
+    final parts = RegExp(r'^(\d{4})-(\d{2})-(\d{2})$').firstMatch(widget.value);
+    _year.text = parts?.group(1) ?? '';
+    final month = int.tryParse(parts?.group(2) ?? '');
+    _month = month != null && month >= 1 && month <= 12 ? month : null;
+    _day.text = parts?.group(3) ?? '';
+  }
+
+  DateTime? get _date {
+    final day = int.tryParse(_day.text);
+    final year = int.tryParse(_year.text);
+    if (day == null ||
+        year == null ||
+        year < 1 ||
+        _year.text.length != 4 ||
+        _month == null) {
+      return null;
+    }
+    final date = DateTime(year, _month!, day);
+    return date.year == year && date.month == _month && date.day == day
+        ? date
+        : null;
+  }
+
+  bool _future(DateTime date) =>
+      date.isAfter(DateUtils.dateOnly(DateTime.now()));
+
+  void _change() {
+    setState(() {});
+    final date = _date;
+    _emitted = date == null || _future(date)
+        ? ''
+        : '${_year.text}-${_month.toString().padLeft(2, '0')}-'
+              '${_day.text.padLeft(2, '0')}';
+    widget.onChanged(_emitted);
+  }
+
+  @override
+  void dispose() {
+    _day.dispose();
+    _year.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final l = AppLocalizations.of(context)!;
+    final date = _date;
+    final complete =
+        _day.text.isNotEmpty && _month != null && _year.text.length == 4;
+    final error = !complete
+        ? null
+        : date == null
+        ? l.kycBirthInvalid
+        : _future(date)
+        ? l.kycBirthFuture
+        : null;
+    final months = DateFormat.MMMM(Localizations.localeOf(context).toString());
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.stretch,
+      children: [
+        Text(l.kycBirth, style: Theme.of(context).textTheme.labelLarge),
+        const SizedBox(height: 8),
+        LayoutBuilder(
+          builder: (context, constraints) {
+            final day = _number(
+              key: 'birth-day',
+              controller: _day,
+              label: l.kycBirthDay,
+              length: 2,
+              autofill: AutofillHints.birthdayDay,
+            );
+            final month = DropdownButtonFormField<int>(
+              key: _monthField,
+              initialValue: _month,
+              isExpanded: true,
+              decoration: InputDecoration(labelText: l.kycBirthMonth),
+              items: [
+                for (var month = 1; month <= 12; month++)
+                  DropdownMenuItem(
+                    value: month,
+                    child: Text(months.format(DateTime(2000, month))),
+                  ),
+              ],
+              onChanged: !widget.enabled
+                  ? null
+                  : (value) {
+                      _month = value;
+                      _change();
+                    },
+            );
+            final year = _number(
+              key: 'birth-year',
+              controller: _year,
+              label: l.kycBirthYear,
+              length: 4,
+              autofill: AutofillHints.birthdayYear,
+            );
+            final scale = MediaQuery.textScalerOf(context).scale(16) / 16;
+            if (constraints.maxWidth < 400 * scale) {
+              return Column(
+                crossAxisAlignment: CrossAxisAlignment.stretch,
+                children: [
+                  day,
+                  const SizedBox(height: 16),
+                  month,
+                  const SizedBox(height: 16),
+                  year,
+                ],
+              );
+            }
+            return Row(
+              crossAxisAlignment: CrossAxisAlignment.start,
+              children: [
+                Expanded(flex: 2, child: day),
+                const SizedBox(width: 12),
+                Expanded(flex: 4, child: month),
+                const SizedBox(width: 12),
+                Expanded(flex: 3, child: year),
+              ],
+            );
+          },
+        ),
+        if (error != null)
+          Padding(
+            padding: const EdgeInsets.only(top: 8),
+            child: Semantics(
+              liveRegion: true,
+              child: Text(
+                error,
+                style: TextStyle(color: Theme.of(context).colorScheme.error),
+              ),
+            ),
+          ),
+      ],
+    );
+  }
+
+  Widget _number({
+    required String key,
+    required TextEditingController controller,
+    required String label,
+    required int length,
+    required String autofill,
+  }) => TextFormField(
+    key: ValueKey(key),
+    controller: controller,
+    enabled: widget.enabled,
+    keyboardType: TextInputType.number,
+    textInputAction: TextInputAction.next,
+    autofillHints: [autofill],
+    inputFormatters: [
+      FilteringTextInputFormatter.digitsOnly,
+      LengthLimitingTextInputFormatter(length),
+    ],
+    decoration: InputDecoration(labelText: label),
+    onChanged: (_) => _change(),
+  );
+}

frontend/app/lib/kyc/profile.dart

@@ -2,6 +2,7 @@ import 'package:flutter/material.dart';
 
 import 'package:sxchnge_kyc/sxchnge_kyc.dart';
 
+import 'birth.dart';
 import 'country.dart';
 
 import '../generated/i18n/app_localizations.dart';
@@ -37,17 +38,11 @@ class ProfileForm extends StatelessWidget {
           onChanged: (value) => update(name: value),
         ),
         const SizedBox(height: 16),
-        TextFormField(
+        BirthField(
           key: const ValueKey('kyc-birth'),
-          initialValue: p.profile.dateOfBirth,
+          value: p.profile.dateOfBirth,
           enabled: !p.busy,
-          keyboardType: TextInputType.datetime,
+          onChanged: (value) => update(birth: value),
-          autofillHints: const [AutofillHints.birthday],
-          decoration: InputDecoration(
-            labelText: l.kycBirth,
-            helperText: l.kycBirthHelp,
-          ),
-          onChanged: (value) => update(birth: value.trim()),
         ),
         const SizedBox(height: 16),
         CountryField(

frontend/app/lib/l10n/en.arb

@@ -160,7 +160,7 @@
   "wRecent": "Recent activity",
   "wSeeAll": "See all",
   "wEmptyActivity": "Your next move starts here. Your transactions will appear below.",
-  "wEmptyAccounts": "No currency accounts have been set up for you yet. Contact support to request account setup.",
+  "wEmptyAccounts": "Your accounts are not ready yet. Try refreshing.",
   "wRefresh": "Refresh",
   "wSource": "From account",
   "wDestination": "To account",
@@ -269,7 +269,11 @@
   "kycProfileHelp": "Enter your details exactly as shown on your identity document.",
   "kycFullName": "Full legal name",
   "kycBirth": "Date of birth",
-  "kycBirthHelp": "YYYY-MM-DD, for example 1990-04-23",
+  "kycBirthDay": "Day",
+  "kycBirthMonth": "Month",
+  "kycBirthYear": "Year",
+  "kycBirthInvalid": "Enter a valid date of birth.",
+  "kycBirthFuture": "Date of birth cannot be in the future.",
   "kycCountry": "Country of residence",
   "kycCountrySelect": "Select a country",
   "kycCountrySearch": "Search countries",

frontend/app/lib/l10n/ru.arb

@@ -160,7 +160,7 @@
   "wRecent": "Последние операции",
   "wSeeAll": "Смотреть все",
   "wEmptyActivity": "Ваш следующий шаг начинается здесь. Здесь появятся ваши операции.",
-  "wEmptyAccounts": "У вас ещё нет валютных счетов. Обратитесь в поддержку за помощью с их открытием.",
+  "wEmptyAccounts": "Ваши счета ещё не готовы. Попробуйте обновить страницу.",
   "wRefresh": "Обновить",
   "wSource": "Со счёта",
   "wDestination": "На счёт",
@@ -269,7 +269,11 @@
   "kycProfileHelp": "Укажите данные точно как в документе, удостоверяющем личность.",
   "kycFullName": "Полное имя по документу",
   "kycBirth": "Дата рождения",
-  "kycBirthHelp": "ГГГГ-ММ-ДД, например 1990-04-23",
+  "kycBirthDay": "День",
+  "kycBirthMonth": "Месяц",
+  "kycBirthYear": "Год",
+  "kycBirthInvalid": "Укажите корректную дату рождения.",
+  "kycBirthFuture": "Дата рождения не может быть в будущем.",
   "kycCountry": "Страна проживания",
   "kycCountrySelect": "Выберите страну",
   "kycCountrySearch": "Поиск страны",

frontend/app/test/birth_test.dart

@@ -0,0 +1,236 @@
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:sxchnge_theme/sxchnge_theme.dart';
+
+import 'package:sxchnge_app/kyc/birth.dart';
+
+import 'package:sxchnge_app/generated/i18n/app_localizations.dart';
+
+void main() {
+  final day = find.byKey(const ValueKey('birth-day'));
+  final year = find.byKey(const ValueKey('birth-year'));
+  final month = find.byType(DropdownButtonFormField<int>);
+
+  Future<void> mount(
+    WidgetTester t,
+    ValueNotifier<String> value, {
+    Locale locale = const Locale('en'),
+    bool enabled = true,
+  }) async {
+    await t.pumpWidget(
+      MaterialApp(
+        theme: SxchngeTheme.light(),
+        locale: locale,
+        localizationsDelegates: AppLocalizations.localizationsDelegates,
+        supportedLocales: AppLocalizations.supportedLocales,
+        home: Scaffold(
+          body: SingleChildScrollView(
+            padding: const EdgeInsets.all(24),
+            child: ValueListenableBuilder<String>(
+              valueListenable: value,
+              builder: (_, date, _) => BirthField(
+                value: date,
+                enabled: enabled,
+                onChanged: (date) => value.value = date,
+              ),
+            ),
+          ),
+        ),
+      ),
+    );
+    await t.pumpAndSettle();
+  }
+
+  Future<void> select(WidgetTester t, String name) async {
+    await t.ensureVisible(month);
+    await t.tap(month);
+    await t.pumpAndSettle();
+    await t.tap(find.text(name).last);
+    await t.pumpAndSettle();
+  }
+
+  testWidgets('enters and corrects a birthday without ISO syntax', (t) async {
+    final value = ValueNotifier('');
+    addTearDown(value.dispose);
+    await mount(t, value);
+    expect(find.text('Date of birth'), findsOneWidget);
+    await t.enterText(day, '23');
+    await select(t, 'April');
+    expect(value.value, '');
+    await t.enterText(year, '1990');
+    await t.pumpAndSettle();
+    expect(value.value, '1990-04-23');
+    await t.enterText(day, '9');
+    await t.pumpAndSettle();
+    expect(value.value, '1990-04-09');
+    await t.enterText(year, '19');
+    await t.pumpAndSettle();
+    expect(value.value, '');
+    // A provider rebuild must retain the other components of an incomplete date.
+    expect(t.widget<TextFormField>(day).controller!.text, '9');
+    expect(find.text('April'), findsOneWidget);
+    await t.enterText(year, '1985');
+    await t.pumpAndSettle();
+    expect(value.value, '1985-04-09');
+  });
+
+  testWidgets('leap dates, impossible days and future dates recover inline', (
+    t,
+  ) async {
+    final value = ValueNotifier('2000-02-29');
+    addTearDown(value.dispose);
+    await mount(t, value);
+    expect(find.text('February'), findsOneWidget);
+    await t.enterText(year, '2001');
+    await t.pumpAndSettle();
+    expect(value.value, '');
+    expect(find.text('Enter a valid date of birth.'), findsOneWidget);
+    expect(t.widget<TextFormField>(day).controller!.text, '29');
+    await t.enterText(year, '2004');
+    await t.pumpAndSettle();
+    expect(value.value, '2004-02-29');
+    expect(find.text('Enter a valid date of birth.'), findsNothing);
+    await t.enterText(day, '31');
+    await select(t, 'April');
+    expect(value.value, '');
+    expect(find.text('Enter a valid date of birth.'), findsOneWidget);
+    await t.enterText(day, '30');
+    await t.enterText(year, '${DateTime.now().year + 1}');
+    await t.pumpAndSettle();
+    expect(value.value, '');
+    expect(find.text('Date of birth cannot be in the future.'), findsOneWidget);
+    await t.enterText(year, '1990');
+    await t.pumpAndSettle();
+    expect(value.value, '1990-04-30');
+    await t.enterText(day, '0');
+    await t.pumpAndSettle();
+    expect(value.value, '');
+    expect(find.text('Enter a valid date of birth.'), findsOneWidget);
+    await t.enterText(day, '1');
+    await t.enterText(year, '0000');
+    await t.pumpAndSettle();
+    expect(value.value, '');
+    expect(find.text('Enter a valid date of birth.'), findsOneWidget);
+  });
+
+  testWidgets(
+    'prefill, external replacement, locale change and clear synchronize',
+    (t) async {
+      final value = ValueNotifier('1990-04-23');
+      addTearDown(value.dispose);
+      await mount(t, value);
+      expect(t.widget<TextFormField>(year).controller!.text, '1990');
+      value.value = '1985-12-09';
+      await t.pumpAndSettle();
+      expect(t.widget<TextFormField>(day).controller!.text, '09');
+      expect(t.widget<TextFormField>(year).controller!.text, '1985');
+      expect(find.text('December'), findsOneWidget);
+      await mount(t, value, locale: const Locale('ru'));
+      expect(find.text('Дата рождения'), findsOneWidget);
+      expect(find.text('декабрь'), findsOneWidget);
+      expect(value.value, '1985-12-09');
+      await select(t, 'апрель');
+      expect(value.value, '1985-04-09');
+      value.value = '';
+      await t.pumpAndSettle();
+      expect(t.widget<TextFormField>(day).controller!.text, '');
+      expect(t.widget<TextFormField>(year).controller!.text, '');
+      expect(find.text('апрель'), findsNothing);
+    },
+  );
+
+  testWidgets('digits and length limits keep each component usable', (t) async {
+    final value = ValueNotifier('1990-04-23');
+    addTearDown(value.dispose);
+    await mount(t, value);
+    await t.enterText(day, '');
+    await t.enterText(day, 'a123');
+    await t.enterText(year, '');
+    await t.enterText(year, 'b19856');
+    await t.pumpAndSettle();
+    expect(t.widget<TextFormField>(day).controller!.text, '12');
+    expect(t.widget<TextFormField>(year).controller!.text, '1985');
+    expect(value.value, '1985-04-12');
+  });
+
+  testWidgets('busy state disables every birthday control', (t) async {
+    final value = ValueNotifier('1990-04-23');
+    addTearDown(value.dispose);
+    await mount(t, value, enabled: false);
+    expect(t.widget<TextFormField>(day).enabled, isFalse);
+    expect(t.widget<TextFormField>(year).enabled, isFalse);
+    expect(t.widget<DropdownButtonFormField<int>>(month).onChanged, isNull);
+    expect(value.value, '1990-04-23');
+  });
+
+  testWidgets('keyboard can traverse, choose month, cancel and edit year', (
+    t,
+  ) async {
+    final value = ValueNotifier('1990-04-23');
+    addTearDown(value.dispose);
+    await mount(t, value);
+    await t.sendKeyEvent(LogicalKeyboardKey.tab);
+    await t.pump();
+    expect(
+      t
+          .widget<EditableText>(
+            find.descendant(of: day, matching: find.byType(EditableText)),
+          )
+          .focusNode
+          .hasFocus,
+      isTrue,
+    );
+    await t.sendKeyEvent(LogicalKeyboardKey.tab);
+    await t.sendKeyEvent(LogicalKeyboardKey.enter);
+    await t.pumpAndSettle();
+    await t.sendKeyEvent(LogicalKeyboardKey.arrowDown);
+    await t.sendKeyEvent(LogicalKeyboardKey.enter);
+    await t.pumpAndSettle();
+    expect(value.value, '1990-05-23');
+    await t.sendKeyEvent(LogicalKeyboardKey.enter);
+    await t.pumpAndSettle();
+    await t.sendKeyEvent(LogicalKeyboardKey.escape);
+    await t.pumpAndSettle();
+    expect(value.value, '1990-05-23');
+    await t.sendKeyEvent(LogicalKeyboardKey.tab);
+    await t.pump();
+    expect(
+      t
+          .widget<EditableText>(
+            find.descendant(of: year, matching: find.byType(EditableText)),
+          )
+          .focusNode
+          .hasFocus,
+      isTrue,
+    );
+  });
+
+  testWidgets(
+    'Russian controls and errors fit 320px with large text and labeled targets',
+    (t) async {
+      t.view.physicalSize = const Size(320, 900);
+      t.view.devicePixelRatio = 1;
+      t.platformDispatcher.textScaleFactorTestValue = 1.6;
+      addTearDown(t.view.resetPhysicalSize);
+      addTearDown(t.view.resetDevicePixelRatio);
+      addTearDown(t.platformDispatcher.clearTextScaleFactorTestValue);
+      final semantics = t.ensureSemantics();
+      final value = ValueNotifier('1990-09-23');
+      addTearDown(value.dispose);
+      await mount(t, value, locale: const Locale('ru'));
+      expect(find.text('сентябрь'), findsOneWidget);
+      expect(t, meetsGuideline(labeledTapTargetGuideline));
+      expect(t, meetsGuideline(androidTapTargetGuideline));
+      await t.enterText(day, '31');
+      await t.pumpAndSettle();
+      expect(find.text('Укажите корректную дату рождения.'), findsOneWidget);
+      await select(t, 'март');
+      expect(value.value, '1990-03-31');
+      expect(t.takeException(), isNull);
+      semantics.dispose();
+    },
+  );
+}

frontend/app/test/kyc_test.dart

@@ -11,6 +11,7 @@ import 'package:sxchnge_analytics/sxchnge_analytics.dart';
 
 import 'package:sxchnge_kyc/sxchnge_kyc.dart';
 
+import 'package:sxchnge_app/kyc/birth.dart';
 import 'package:sxchnge_app/kyc/country.dart';
 import 'package:sxchnge_app/main.dart';
 import 'package:sxchnge_app/providers/locale.dart';
@@ -66,10 +67,16 @@ void main() {
     return service;
   }
 
-  Future<void> submit(WidgetTester t) async {
+  Future<void> profile(WidgetTester t) async {
     await tap(t, find.byKey(const ValueKey('kyc-start')));
     await t.enterText(find.byKey(const ValueKey('kyc-name')), 'Example Person');
-    await t.enterText(find.byKey(const ValueKey('kyc-birth')), '1990-04-23');
+    await t.enterText(find.byKey(const ValueKey('birth-day')), '23');
+    await tap(t, find.byType(DropdownButtonFormField<int>));
+    // The month label follows the selected app locale.
+    await tap(t, find.textContaining(RegExp(r'^(April|апрель)$')).last);
+    await t.enterText(find.byKey(const ValueKey('birth-year')), '1990');
+    await t.pumpAndSettle();
+    expect(t.widget<BirthField>(find.byType(BirthField)).value, '1990-04-23');
     await tap(
       t,
       find.descendant(
@@ -85,6 +92,10 @@ void main() {
       'PL',
     );
     await t.pumpAndSettle();
+  }
+
+  Future<void> submit(WidgetTester t) async {
+    await profile(t);
     await tap(t, find.byKey(const ValueKey('pick-passport')));
     await tap(t, find.byKey(const ValueKey('kyc-next')));
     await tap(t, find.byKey(const ValueKey('pick-selfie')));
@@ -93,6 +104,41 @@ void main() {
     await tap(t, find.byKey(const ValueKey('kyc-submit')));
   }
 
+  testWidgets(
+    'invalid birthday blocks advancing and valid birthday survives Back',
+    (t) async {
+      await open(t);
+      await profile(t);
+      await tap(t, find.byKey(const ValueKey('pick-passport')));
+      final next = find.byKey(const ValueKey('kyc-next'));
+      await t.enterText(find.byKey(const ValueKey('birth-day')), '31');
+      await t.pumpAndSettle();
+      expect(t.widget<FilledButton>(next).onPressed, isNull);
+      expect(find.text('Enter a valid date of birth.'), findsOneWidget);
+      await t.enterText(find.byKey(const ValueKey('birth-day')), '23');
+      await t.pumpAndSettle();
+      expect(t.widget<FilledButton>(next).onPressed, isNotNull);
+      await tap(t, next);
+      await tap(t, find.text('Back'));
+      expect(t.widget<BirthField>(find.byType(BirthField)).value, '1990-04-23');
+      expect(
+        t
+            .widget<TextFormField>(find.byKey(const ValueKey('birth-day')))
+            .controller!
+            .text,
+        '23',
+      );
+      expect(find.text('April'), findsOneWidget);
+      expect(
+        t
+            .widget<TextFormField>(find.byKey(const ValueKey('birth-year')))
+            .controller!
+            .text,
+        '1990',
+      );
+    },
+  );
+
   testWidgets('two photos, review, pending and approval with service limits', (
     t,
   ) async {