Authentication problem

         private void Awake()
         {
             PlayGamesPlatform.DebugLogEnabled = true;
             PlayGamesPlatform.Activate(); 
         }
 
         
         private void Start()
         {
             Social.localUser.Authenticate(success => Debug.Log(success));
 
             var config =
                 new PlayGamesClientConfiguration.Builder().Build();
             PlayGamesPlatform.InitializeInstance(config);
             //PlayGamesPlatform.Instance.Authenticate(success => Debug.Log(success));
 
         }
 
         private void OnClick()
         {
             Social.ReportScore(12345, "CgkI9IGIn-kSEAIQCQ", success =>
             {
                 // handle success or failure
             });
 
             PlayGamesPlatform.Instance.ShowLeaderboardUI("CgkI9IGIn-kSEAIQCQ");
         }
     }
 }

1. ERROR: ReportScore can only be called after authentication.

2. ERROR: ShowLeaderboardUI can only be called after authentication.

Update1: It might be because of Soomla's integration, not sure, just an assumption, cause already saw a few posts having the same problem.

Update2: Linked question which may help you determine what I'm doing wrong.

What am I forgetting?

If you're not sure what could the problem be, please suggest actions which I can take in order to determine what the problem is on comments.