Angular Firebase身份验证未找到提供程序

Question

我正在尝试在我的角度应用程序上使用Firebase身份验证使用身份验证。为此，我创建了一个身份验证服务，身份验证防护和前端来登录/注册。不幸的是，我遇到以下错误：

NullInjectorError：R3InjectorError（AppModule）[AuthGuard-> AuthService-> AngularFireAuth-> AngularFireAuth-> AngularFireAuth]：

这是我的app.module：

import { AngularFireModule } from '@angular/fire';
import { AngularFirestoreModule } from '@angular/fire/firestore';
import { AngularFireAuthModule } from '@angular/fire/auth';
import { UserProfileComponent } from './user-profile/user-profile.component';
import {AuthService} from './auth.service';
import {AuthGuard} from './auth.guard';


@NgModule({
  declarations: [
     AppComponent,

    ],
    imports: [

       AngularFireModule.initializeApp(environment.firebase),
       AngularFirestoreModule,
       AngularFireAuthModule

     // imports firebase/auth, only needed for auth features
  ],
 providers: [ AngularFireAuthModule, AuthService, AuthGuard],
entryComponents: [LocationsFilterBottomSheetComponent, QrCodeBottomSheetComponent, FilterVouchersBottomSheetComponent],

 bootstrap: [AppComponent]
 })
export class AppModule {
 }