Flutter Navigator acting weird - flutter

Question

I am trying to implement navigator 2.0 using flutter bloc but the problem is when I add new event and update state it does not rebuild even tho the bloc builder is working but when I hot reload all the previous pages in the list stack up and I can press back they all pop and when i reach at the first page it again stop rebuilding. I am posting a some chunk of code.
Here is the delegate class
class MyRouterDelegate extends RouterDelegate
with ChangeNotifier, PopNavigatorRouterDelegateMixin {
bool showOtherPage = false;
#override
final GlobalKey<NavigatorState> navigatorKey;
MyRouterDelegate() : navigatorKey = GlobalKey<NavigatorState>();
#override
Widget build(BuildContext context) {
return BlocBuilder<AuthenticationBloc, AuthenticationState>(
builder: (context, authenticationState) {
print(authenticationState.pages);
return Navigator(
key: navigatorKey,
pages: authenticationState.pages,
onPopPage: (route, result) {
if (!route.didPop(result)) return false;
BlocProvider.of<AuthenticationBloc>(context).add(UserLogoutEvent());
return true;
},
);
},
);
}
#override
Future<void> setNewRoutePath(configuration) async => null;
}
Here is my bloc
class AuthenticationBloc
extends Bloc<AuthenticationEvent, AuthenticationState> {
AuthenticationBloc()
: super(AuthenticationState(pages: [
MaterialPage(child: MyConnexionWidget(), key: ValueKey('my page'))
]));
#override
Stream<AuthenticationState> mapEventToState(
AuthenticationEvent event) async* {
switch (event.runtimeType) {
case UserLoginEvent:
final oldState = state.pages;
oldState
.add(MaterialPage(child: MyHomeWidget(), key: ValueKey('home')));
yield AuthenticationState(pages: oldState);
break;
case UserLogoutEvent:
final oldState = state.pages;
oldState.removeLast();
yield AuthenticationState(pages: oldState);
break;
}
}
}
// Authentication events
abstract class AuthenticationEvent {}
class UserLogoutEvent extends AuthenticationEvent {}
class UserLoginEvent extends AuthenticationEvent {}
// Authentication states
class AuthenticationState {
final List<Page> pages;
const AuthenticationState({required this.pages});
}
First page
class MyConnexionWidget extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Navigator 2.0 101 - Connexion screen'),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
FlatButton(
child: Container(
padding: EdgeInsets.all(8.0),
color: Colors.greenAccent,
child: Text('Click me to connect.'),
),
onPressed: () => BlocProvider.of<AuthenticationBloc>(context)
.add(UserLoginEvent()),
)
],
),
),
);
}
}