[firebase_auth] "Unhandled Exception: [firebase_auth/unknown] null"

[muddi900]

my main()

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp();

  if (IS_EMULATOR) {
    if (!kIsWeb) {
      String host = !Platform.isAndroid ? 'localhost' : '10.0.2.2';
      await FirebaseAuth.instance.useAuthEmulator(host, 9099);
      FirebaseFirestore.instance.settings = Settings(
        host: '$host:8080',
        sslEnabled: false,
        persistenceEnabled: false,
      );
      await fbStorage.FirebaseStorage.instance.useStorageEmulator(host, 9199);
      if (Platform.isIOS) timeDilation = 2.0;
    } else {
      await FirebaseAuth.instance.useAuthEmulator('localhost', 9099);
      FirebaseFirestore.instance.useFirestoreEmulator('localhost', 8080);
      await fbStorage.FirebaseStorage.instance
          .useStorageEmulator('localhost', 9199);
    }
  }

  runApp(const MyApp());
}

and the firebase auth login code.

void _submitLogin(String email, String password) async {
      final _auth = FirebaseAuth.instance;
      UserCredential user;
      final firestore = FirebaseFirestore.instance;
      bool haveDaysSelected = !_daysOfWeek.values.every((element) => !element);
      bool haveImage = _profileImage != null;
      bool haveCourts = _tennisCourts.isNotEmpty;


      if (_isSignup) {
        user = await _auth.createUserWithEmailAndPassword(
          email: email,
          password: password,
        );

       /*unrelated Firestore logic*/
 
        return;
      }

await _auth.signInWithEmailAndPassword(email: email, password: password);

The firebase app is being initialized in the main. The code worked as of last week. The error is thrown at sign-up or login. I do not know what changed.