UNET: Lobby players not spawning on joining client

I amextending the NetworkLobbyManager to create a game lobby:

public class NLMExtender : NetworkLobbyManager
{
  public override void OnLobbyStartHost()
  {
    GameObject.FindWithTag("MultiplayerRoom").GetComponent<MultiplayerRoom>().isHost = true;
  }
}

I create a match like this which creates lobby players on the scene:

  /// <summary>
  /// Create a match
  /// </summary>
  public void CreateMatch()
	{
    networkMatch = gameObject.AddComponent<NetworkMatch>();
    
    CreateMatchRequest create = new CreateMatchRequest();
    create.name = "MS_" + Guid.NewGuid().ToString("N");
    create.size = 2;
    create.advertise = true;
    create.password = "";

    networkMatch.CreateMatch(create, OnMatchCreate);
	}

  /// <summary>
  /// When match is being created
  /// </summary>
  /// <param name="matchResponse"></param>
  public void OnMatchCreate(CreateMatchResponse matchResponse)
  {
    if (matchResponse.success)
    {
      matchInfo = new MatchInfo(matchResponse);
      Utility.SetAccessTokenForNetwork(matchResponse.networkId, new NetworkAccessToken(matchResponse.accessTokenString));
      networkLobbyManager.StartHost(matchInfo);
    }
    else {
      Debug.LogError("Create match failed");
    }
  }

And I join a room like this which does not create the lobby players on the client:

  /// <summary>
  /// Connects to the lobby
  /// </summary>
  public void ConnectToRoom(GameObject gameList, MatchDesc match)
  {
    networkMatch = gameObject.AddComponent<NetworkMatch>();
    gameList.SetActive(false);
    networkMatch.JoinMatch(match.networkId, "", OnMatchJoined); // connect to the room
  }

  /// <summary>
  /// When a lobby has been joined
  /// </summary>
  /// <param name="matchJoin">Result of joining a lobby</param>
  public void OnMatchJoined(JoinMatchResponse matchInfo)
  {
    if (matchInfo.success)
    {
      networkLobbyManager.StartClient(new MatchInfo(matchInfo));
    }
    else
    {
      Debug.LogError("Join match failed");
    }
  }

Is there anything here that can be the reason for this? Because when I added the NetworkLobbyManager to the game object trough the editor it worked, but not when I extend this class to my own script (for the ability to override). Am I missing something that automatically happens when doing it trough the editor?

This is how it looks in the editor today:

The error message which most probably is related to my problem:

RegisterHandler id:45
handler:OnClientAddPlayerFailedMessage
UnityEngine.Networking.NetworkManager:StartClient(MatchInfo)
MultiplayerRoom:OnMatchJoined(JoinMatchResponse)
(at Assets/Scripts/GUI/Menus/Multiplayer/MultiplayerRoom.cs:81)
UnityEngine.Networking.Match.c__Iterator0`1:MoveNext()

I experiencing a same issue … Did u solved it ?.. if yes pls help me