getIt error NotificationRepositoryImpl depends on unregistered type NotificationService Warning and Error

Question

I know there are other same questions but I couldn't find the solution. The NotificationRepository depends on NotificationService and it depends on Flutter local Notifications plugin instance.

Initialization 
final GetIt getIt = GetIt.instance;

@InjectableInit(
  initializerName: 'init', // default
  preferRelativeImports: true, // default
  asExtension: true,
)
void configureDependencies() => getIt.init(); 

I have called it in main

@module
abstract class InjectableModule {
  // for other use
  @lazySingleton
  Dio dio() => ...

  @lazySingleton
  FlutterLocalNotificationsPlugin getLocalNotification() =>
      FlutterLocalNotificationsPlugin();
}

this is the module that I have used to put FLNotification to Notification Service

abstract class NotificationService {
 // required functions...
}


@LazySingleton(as: NotificationService)
class NotificationServiceImp implements NotificationService {
  final FlutterLocalNotificationsPlugin flutterLocalNotificationsPlugin;

  NotificationServiceImp(this.flutterLocalNotificationsPlugin);
  .....
}

abstract class NotificationRepository {
  ....
}

@LazySingleton(as: NotificationRepository)
class NotificationRepositoryImpl implements NotificationRepository {
  final NotificationService _notificationService;
  NotificationRepositoryImpl(this._notificationService);
  ....
}

This is the warning I get when I run build runner

[WARNING] injectable_generator:injectable_config_builder on lib/di/get_it.dart:
Missing dependencies in statedemo/di/get_it.dart

[NotificationRepositoryImpl] depends on unregistered type [NotificationService] from package:statedemo/data/services/notification_serivce_imp.dart

This is the error that I get when I run the code 
Bad state: GetIt: Object/factory with type NotificationService is not registered inside GetIt.
(Did you accidentally do GetIt sl=GetIt.instance(); instead of GetIt sl=GetIt.instance;
Did you forget to register it?)

GetIt works fine with the other registration that I have done in this project for Dio. I just wanted to implement notification feature. This feature works fine when I try to implement Singleton pattern for notification service manually. I have also tried named Instance and I get this

Bad state: GetIt: Object/factory with with name NotificationServiceImp and type NotificationService       
is not registered inside GetIt.
(Did you accidentally do GetIt sl=GetIt.instance(); instead of GetIt sl=GetIt.instance;
Did you forget to register it?)

Thanks for giving your time. If you want more information I can provide.