Flutter: No Firebase App '[DEFAULT]' has been created - when I stream AUTH

I am working on a project and encountered a problem. I have already initialised Firebase in the main.dart as so:

class _AppState extends State<App> {
  final Future<FirebaseApp> _initialization = Firebase.initializeApp();

  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
      // Initialize FlutterFire:
      future: _initialization,
      builder: (context, snapshot) {
        if (snapshot.hasError) {}

        if (snapshot.connectionState == ConnectionState.done) {
          return MaterialApp(
            routes: appRoutes,
            theme: appTheme,
          );
        }

        // return const MaterialApp(home: LoadingScreen());
        return const Directionality(
            textDirection: TextDirection.ltr, child: Text("Loading"));
      },
    );
  }

Everything well so far, the app runs and firebase initialises as it should. Routs set like this:

'/': (context) => const HomePage(),
'/login': (context) => const LoginPage(),

So, we will naturally go to the home page. Here is where the error comes in. Here in the home page, I want to listen at a stream if the user is logged in or not. The problem is that when I initialise the stream I get the following error: [core/no-app] No Firebase App '[DEFAULT]' has been created - call Firebase.initializeApp()

Here is the code of the home page:

class HomePage extends StatelessWidget {
  const HomePage({super.key});

  @override
  Widget build(BuildContext context) {
    return StreamBuilder(
      stream: AuthService().userStream,
      builder: (context, snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          return const Text("loading");
        } else if (snapshot.hasError) {
          return const Center(
            child: Text("Error"),
          );
        } else if (snapshot.hasData) {
          return const ClientDashboardPage();
        } else {
          print("nodata");
          return const LoginPage();
        }
      },
    );
  }
}

And here is the Auth File:

import 'package:firebase_auth/firebase_auth.dart';

class AuthService {
  final userStream = FirebaseAuth.instance.authStateChanges();
  final user = FirebaseAuth.instance.currentUser;
}

So all I am doing is listening to the stream and that error is thrown. If I remove the whole home page and just put a text, I see the text. So the error is clearly from the Auth Stream. I have searched online about this error but the most majority say that this is due to firebase not being initialised. If it was not in my case, I would not even come to the home page since this is being checked in the main.dart.

What solutions / ideas do you guys have? Thank you so much for the help!

Here is the full error:

════════ Exception caught by widgets library ═══════════════════════════════════
The following FirebaseException was thrown building HomePage(dirty):
[core/no-app] No Firebase App '[DEFAULT]' has been created - call Firebase.initializeApp()

The relevant error-causing widget was
HomePage
routes.dart:7
When the exception was thrown, this was the stack
#0      MethodChannelFirebase.app
method_channel_firebase.dart:193
#1      Firebase.app
firebase.dart:56
#2      FirebaseAuth.instance
firebase_auth.dart:44
#3      new AuthService
auth.dart:4
#4      HomePage.build
home.dart:12
#5      StatelessElement.build
framework.dart:5367
#6      ComponentElement.performRebuild
framework.dart:5297
#7      Element.rebuild
framework.dart:5016
#8      ComponentElement._firstBuild
framework.dart:5279
#9      ComponentElement.mount
framework.dart:5273
...     Normal element mounting (220 frames)
#229    Element.inflateWidget
framework.dart:4182
#230    MultiChildRenderObjectElement.inflateWidget
framework.dart:6569
#231    MultiChildRenderObjectElement.mount
framework.dart:6581
...     Normal element mounting (435 frames)
#666    Element.inflateWidget
framework.dart:4182
#667    Element.updateChild
framework.dart:3701
#668    ComponentElement.performRebuild
framework.dart:5322
#669    StatefulElement.performRebuild
framework.dart:5462
#670    Element.rebuild
framework.dart:5016
#671    BuildOwner.buildScope
framework.dart:2779
#672    WidgetsBinding.drawFrame
binding.dart:916
#673    RendererBinding._handlePersistentFrameCallback
binding.dart:360
#674    SchedulerBinding._invokeFrameCallback
binding.dart:1297
#675    SchedulerBinding.handleDrawFrame
binding.dart:1227
#676    SchedulerBinding._handleDrawFrame
binding.dart:1085
#677    _invoke (dart:ui/hooks.dart:170:13)

I discovered that adding options: DefaultFirebaseOptions.currentPlatform, solved the issue

final Future<FirebaseApp> _initialization = Firebase.initializeApp(
    options: DefaultFirebaseOptions.currentPlatform,
  );