Не работает скрипт связанный с Photon

 using System.Collections; 
using Photon.Pun; 
using Photon.Realtime; 
using UnityEngine; 
using UnityEngine.SceneManagement; 
 
public class GameManager : MonoBehaviourPunCallbacks 
{ 
    public void Leave() 
    { 
        PhotonNetwork.LeaveRoom(); 
    } 
 
    public override void OnLeftRoom() 
    { 
        SceneManager.LoadScene(0); 
    } 
 
    public override void OnPlayerEnteredRoom(Player newPlayer) 
    { 
        Debug.LogFormat("Player {0} entered room", newPlayer.NickName); 
    } 
 
    public override void OnPlayerLeftRoom(Player otherPlayer) 
    { 
        Debug.LogFormat("Player {0} exited room", otherPlayer.NickName); 
    } 
} 
ошибки Assets\GameManager.cs(19,26): error CS0115: 'GameManager.OnPlayerEnteredRoom(Player)': no suitable method found to override 
и Assets\GameManager.cs(24,26): error CS0115: 'GameManager.OnPlayerLeftRoom(Player)': no suitable method found to override