diff --git a/src/app/authentication.service.ts b/src/app/authentication.service.ts
index e53a9cc82e4a51d55dee61ec1aea42fdf64882af..9ac65824d3f26c3054a34b73d69a32b59b9ded2d 100644
--- a/src/app/authentication.service.ts
+++ b/src/app/authentication.service.ts
@@ -6,6 +6,11 @@ import { UserRole } from './user-roles.enum';
 import { DataStoreService } from './data-store.service';
 import { HttpClient, HttpHeaders } from '@angular/common/http';
 import { ClientAuthentication } from './client-authentication';
+import { AuthProvider } from './auth-provider';
+import { NotificationService } from './notification.service';
+import { catchError, tap } from 'rxjs/operators';
+import { ErrorHandlingService } from './error-handling.service';
+import { ClientAuthentication } from './client-authentication';
 
 // TODO: connect to API
 @Injectable()
@@ -24,7 +29,6 @@ export class AuthenticationService {
     headers: new HttpHeaders({})
   };
 
-
   constructor(private dataStoreService: DataStoreService,
               private http: HttpClient) {
     if (dataStoreService.has(this.STORAGE_KEY)) {