Необработанное исключение: setState() вызывается после dispose()

Я пытаюсь получать уведомления в своем приложении флаттера, используя Firebase Messaging, чтобы отображать их в приложении, но я продолжаю получать сообщение об ошибке:

/FLTFireMsgReceiver( 6823): broadcast received for message
E/flutter ( 6823): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: setState() called after dispose(): _TipsState#aa4df(lifecycle state: defunct, not mounted)
E/flutter ( 6823): This error happens if you call setState() on a State object for a widget that no longer appears in the widget tree (e.g., whose parent widget no longer includes the widget in its build). This error can occur when code calls setState() from a timer or an animation callback.
E/flutter ( 6823): The preferred solution is to cancel the timer or stop listening to the animation in the dispose() callback. Another solution is to check the "mounted" property of this object before calling setState() to ensure the object is still in the tree.
E/flutter ( 6823): This error might indicate a memory leak if setState() is being called because another object is retaining a reference to this State object after it has been removed from the tree. To avoid memory leaks, consider breaking the reference to this object during dispose().
E/flutter ( 6823): #0      State.setState.<anonymous closure> (package:flutter/src/widgets/framework.dart:1085:9)
E/flutter ( 6823): #1      State.setState (package:flutter/src/widgets/framework.dart:1120:6)
E/flutter ( 6823): #2      _TipsState.getNotification.<anonymous closure> (package:stock_baba/Screens/Tips.dart:38:9)
E/flutter ( 6823): #3      _rootRunUnary (dart:async/zone.dart:1434:47)
E/flutter ( 6823): #4      _CustomZone.runUnary (dart:async/zone.dart:1335:19)
E/flutter ( 6823): #5      _CustomZone.runUnaryGuarded (dart:async/zone.dart:1244:7)
E/flutter ( 6823): #6      _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:341:11)
E/flutter ( 6823): #7      _DelayedData.perform (dart:async/stream_impl.dart:591:14)
E/flutter ( 6823): #8      _StreamImplEvents.handleNext (dart:async/stream_impl.dart:706:11)
E/flutter ( 6823): #9      _PendingEvents.schedule.<anonymous closure> (dart:async/stream_impl.dart:663:7)
E/flutter ( 6823): #10     _rootRun (dart:async/zone.dart:1418:47)
E/flutter ( 6823): #11     _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6823): #12     _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter ( 6823): #13     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
E/flutter ( 6823): #14     _rootRun (dart:async/zone.dart:1426:13)
E/flutter ( 6823): #15     _CustomZone.run (dart:async/zone.dart:1328:19)
E/flutter ( 6823): #16     _CustomZone.runGuarded (dart:async/zone.dart:1236:7)
E/flutter ( 6823): #17     _CustomZone.bindCallbackGuarded.<anonymous closure> (dart:async/zone.dart:1276:23)
E/flutter ( 6823): #18     _microtaskLoop (dart:async/schedule_microtask.dart:40:21)
E/flutter ( 6823): #19     _startMicrotaskLoop (dart:async/schedule_microtask.dart:49:5)

Класс PushNotification — это простой класс со строковыми полями title, body, dataTitle и dataBody. Мой код выглядит следующим образом:

class _TipsState extends State<Tips> {
  final FirebaseMessaging _firebaseMessaging = FirebaseMessaging.instance;
  final List<PushNotification> messages = [];
  PushNotification? _notificationInfo;

  @override
  void initState() {
    getNotification();
    super.initState();
  }

  void getNotification() async {
    NotificationSettings settings =
        await _firebaseMessaging.requestPermission();

    if (settings.authorizationStatus == AuthorizationStatus.authorized) {
      print("Permission granted!");

      FirebaseMessaging.onMessage.listen((RemoteMessage message) {
        PushNotification notification = PushNotification(
            title: message.notification?.title,
            body: message.notification?.body,
            dataTitle: message.data['title'],
            dataBody: message.data['body']);

        setState(() {
          _notificationInfo = notification;
        });

        if (notification != null) {
          showSimpleNotification(Text(_notificationInfo!.title!),
              duration: Duration(seconds: 2),
              subtitle: Text(_notificationInfo!.body!));
        }
        print(notification);
        print(message.data);
      });
    } else {
      print("Permission declined!");
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: messages.isEmpty
          ? Container()
          : ListView(
              children: [Text(messages[0].title!)],
            ),
    );
  }
}

Я попытался обернуть setState() с помощью mount(), но это не сработало.

Как я могу решить эту проблему и отображать входящие уведомления в своем приложении?