Flutter Provider: notifyListeners does not update AlertDialog widget

main.dart

/// https://dartpad.dev/f542682880bf16d81d6f6518fa15b11f
/// Answer to the Stack Overflow question: https://stackoverflow.com/questions/71468724/flutter-provider-notifylisteners-does-not-update-alertdialog-widget
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

const Color darkBlue = Color.fromARGB(255, 18, 32, 47);

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData.dark().copyWith(
        scaffoldBackgroundColor: darkBlue,
      ),
      debugShowCheckedModeBanner: false,
      home: ChangeNotifierProvider(
        create: (_) => ServicesProvider(),
        child: const Scaffold(
          body: Center(
            child: MyWidget(),
          ),
        ),
      ),
    );
  }
}

class MyWidget extends StatelessWidget {
  const MyWidget();

  showTextDialog(BuildContext context) {
    final myModel = context.read<ServicesProvider>();

    return showDialog(
      context: context,
      builder: (_) => ChangeNotifierProvider.value(
        value: myModel,
        child: MyDialog(),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      child: const Text('Show modal'),
      onPressed: () => showTextDialog(context),
    );
  }
}

class MyDialog extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final myModel = context.watch<ServicesProvider>();

    return AlertDialog(
      content: IntrinsicHeight(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Row(
              children: [
                Radio(
                  value: '0',
                  groupValue: myModel.paymentMethod,
                  onChanged: (value) => myModel.setPaymentMethod('0'),
                  activeColor: Colors.blue,
                  toggleable: true,
                ),
                const SizedBox(width: 5.0),
                const Text("Radio Button 1"),
              ],
            ),
            const SizedBox(height: 10.0),
            Row(
              children: [
                Radio(
                  value: '1',
                  groupValue: myModel.paymentMethod,
                  onChanged: (value) => myModel.setPaymentMethod('1'),
                  activeColor: Colors.blue,
                  toggleable: true,
                ),
                const SizedBox(width: 5.0),
                const Flexible(child: Text("Radio Button 2")),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

class ServicesProvider extends ChangeNotifier {
  String _paymentMethod = '0';

  String get paymentMethod => _paymentMethod;

  void setPaymentMethod(String method) {
    _paymentMethod = method;

    notifyListeners();
  }
}