Firebase authentication issue

Hi, i have an issue with the authentication in firebase. I'm actually using unity 2019.2 and the firebase sdk 6.6.0. Here the code i use for authentication

Code (CSharp):

1.  
2. public void Login(string username, string password, Action callback)
3.     {
4.         auth.SignInWithEmailAndPasswordAsync(username, password).ContinueWith(task =>
5.         {
6.             if (task.IsCanceled)
7.             {
8.                 InfoPanel.main.ShowError(1);
9.                 return;
10.             }
11.             if (task.IsFaulted)
12.             {  
13.                 InfoPanel.main.ShowMessage(3);
14.                 return;
15.             }
16.  
17.             if (auth.CurrentUser.IsEmailVerified)
18.             {
19.                 callback?.Invoke();
20.             }
21.             else
22.             {
23.                 InfoPanel.main.ShowError(2);
24.             }
25.         }, TaskScheduler.FromCurrentSynchronizationContext());
26.     }
27.  
28. private void AuthStateChanged(object sender, EventArgs eventArgs)
29.    {
30.        if (auth.CurrentUser != CurrentUser)
31.        {
32.            bool signedIn = CurrentUser != auth.CurrentUser && auth.CurrentUser != null;
33.            if (!signedIn && CurrentUser != null)
34.            {              
35.                LoadScene(StringRepository.LOGIN_SCENE);
36.            }
37.            CurrentUser = auth.CurrentUser;
38.            if (signedIn)
39.            {  
40.                userRef = database.GetReference(USERS).Child(CurrentUser.UserId);        
41.                LoadScene(StringRepository.MENU_SCENE, true);
42.            }
43.        }
44.    }
45.  

The problem is that on Android i have a long delay(~1min) before the scene starts loading. Do you have any idea on how to solve this issue? Thanks

 

I came here looking for a resolution for the delay problem although I'm not using Unity, let me know if you ever resolved this, but my app doesn't log on at all, it just sits there