I’m developing a multiplayer game in Unity using Firebase Realtime Database for data synchronization between players. In my setup, both players interact with the game through the same GameController script instance.

The issue I’m encountering is that player 2 is unable to interact with the game or see updates to game state, while player 1 (the host) can interact with the game as expected. Here’s a summary of the problem:

Setup: I have a GameController script that handles game logic and data management for both players. Player 1 creates the game room, and player 2 joins the room.
Data Synchronization: The GameController script communicates with Firebase Realtime Database to synchronize game state between players, including player scores, current turn, selected topic, etc.
Problem: After player 2 joins the game, they are not able to submit answers, see the selected topic, or receive updates to game state. It seems like the data retrieval and update methods are not being executed properly for player 2.

public class GameController : MonoBehaviour
{
    
    public static GameController instance;
    public FirebaseFunctionsHandler firebaseHandler;

    public DatabaseReference databaseReference;
    private FirebaseFunctions functions;

    public TextMeshProUGUI timerText;
    public TextMeshProUGUI topicText;
    public TMP_InputField playerInput;
    public TextMeshProUGUI resultText;
    public TextMeshProUGUI player1ScoreText;
    public TextMeshProUGUI player2ScoreText;
    public TextMeshProUGUI player1nameText;
    public TextMeshProUGUI player2nameText;
    public TextMeshProUGUI invalidWordText;
    public TextMeshProUGUI TurnLabel;
    public Button submitButton;

    public AudioSource correctSound;
    public AudioSource incorrectSound;

    private string selectedTopic;
    private List<string> validWords;
    private List<string> usedWords = new List<string>();
    private int player1Score = 0;
    private int player2Score = 0;
    bool wordExists;

    private bool gameActive = true;
    private bool player1Turn = true; // Track whose turn it is
    private float originalTimer = 10f; // Store the original timer value
    private float timer; // Timer variable

    private int player1Coins = 0;
    private int player2Coins = 0;
    public GameOverController gameOverController;

    private MatchmakingManager matchmakingManager;

    private TopicManager.TopicTree topicTree;
    
    void Start()
    {
        

        topicTree = TopicManager.Instance.topicTree;
        TopicManager.Instance.InitializeTopics();

        databaseReference = FirebaseDatabase.DefaultInstance.RootReference;
        functions = FirebaseFunctions.DefaultInstance;
        matchmakingManager = FindObjectOfType<MatchmakingManager>();
        if (matchmakingManager == null)
        {
            Debug.LogError("MatchmakingManager not found in the scene.");
            return;
        }
       
        submitButton.onClick.AddListener(submitAnswer3);
        StartCoroutine(PlayGame());

      

        FetchAndDisplayUsername();
       FetchAndDisplayPlayer2Name();
       
        
        
    }


    IEnumerator PlayGame()
    {
        
    
        FetchAndDisplaySelectedTopic(RoomManager.CurrentRoomId);
       

        while (gameActive)
        {
            timer = originalTimer; // Reset the timer
            UpdateResultText(); // Update result text to indicate the current player's turn
            
            yield return StartCoroutine(PlayerTurn());
            if (!gameActive) break;
        }

        DisplayScores();
        
    } public async void submitAnswer3()
  {

      string currentInput = playerInput.text.ToLower();
      currentInput = NormalizeWord(currentInput);
      Debug.Log("Current Input: " + currentInput);
      Debug.Log("Selected Topic: " + selectedTopicManager.selectedTopic);
     wordExists = await CallCloudFunction(selectedTopicManager.selectedTopic, currentInput);
      if (wordExists)
      {
          // The word exists in the database
          Debug.Log("Word exists in the database from word exist .");
          UpdateScore();
          resultText.text = "Correct!";
          SwitchTurn();
          timer = originalTimer;
          correctSound.Play();
          UpdateUsedWordsInDatabase(RoomManager.CurrentRoomId);
      }
      else
      {
          // The word does not exist in the database
          Debug.LogWarning("Word does not exist in the database from word exist.");
          invalidWordText.text = ArabicFixer.Fix("خطا,كلمة لا تتعلق بالموضوع");
          invalidWordText.gameObject.SetActive(true);
          gameActive = false;
          timer = 0f; // Set the timer to zero when a wrong answer is submitted
          incorrectSound.Play();
          DetermineWinner();
      }
      DisplayScores();
  }
    async void FetchAndDisplayUsername()
{
    string userId = FirebaseAuth.DefaultInstance.CurrentUser.UserId;
    DataSnapshot snapshot = await databaseReference.Child("users").Child(userId).GetValueAsync();

    if (snapshot.Exists)
    {
        UserProfile userProfile = JsonUtility.FromJson<UserProfile>(snapshot.GetRawJsonValue());
        string username = userProfile.username;

        // Display the username in the UI
      player1nameText.text =   username ;
    }
    else
    {
        Debug.LogError("User profile not found in the database.");
    }
}

async void FetchAndDisplayPlayer2Name()
{
    // Fetch the player 2 ID from the gameRooms node
    DataSnapshot roomSnapshot = await databaseReference.Child("gameRooms").Child(RoomManager.CurrentRoomId).Child("players").GetValueAsync();
    if (roomSnapshot.Exists && roomSnapshot.HasChild("player2"))
    {
        string player2Id = roomSnapshot.Child("player2").Value.ToString();

        // Fetch the player 2 name from the database
        DataSnapshot playerSnapshot = await databaseReference.Child("users").Child(player2Id).GetValueAsync();

        if (playerSnapshot.Exists)
        {
            UserProfile userProfile = JsonUtility.FromJson<UserProfile>(playerSnapshot.GetRawJsonValue());
            string player2Name = userProfile.username;

            player2nameText.text = player2Name;
            // Display the player 2 name in the UI or wherever needed
            Debug.Log("Player 2 id: " + player2Id);
        }
        else
        {
            Debug.LogError("Player 2 profile not found in the database.");
        }
    }
    else
    {
        Debug.LogError("Player 2 ID not found in the gameRooms node.");
    }
}

I’ve checked the following:

Data retrieval methods (FetchAndDisplayPlayer2Name, FetchAndDisplaySelectedTopic, etc.) are being called and executed properly.
Data update methods (UpdateUsedWordsInDatabase, UpdateScoreInDatabase, etc.) are correctly updating the data in the database for both players.
There are no access control restrictions or errors in the database rules that might be causing the issue.
I’m looking for suggestions on how to debug and fix this issue. Any insights or tips on ensuring proper data synchronization between players in a Firebase Realtime Database setup would be greatly appreciated.

Thank you in advance for your help!