Photon issue

I have a problem with my photon. I was following this tutorial:

and reached 4 minutes where a problem occured. It doesn’t load into the lobby scene. The scene’s name is correct and everything and I have tried everything I could come up with.

Here is my script and I hoping one of you guys could help me find the issue

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using Photon.Pun;
using UnityEngine.SceneManagement;

public class ConnectToServer : MonoBehaviourPunCallbacks
{

private void start()
{
PhotonNetwork.ConnectUsingSettings();
}

public override void OnConnectedToMaster()
{
PhotonNetwork.JoinLobby();
}

public override void OnJoinedLobby()
{
SceneManager.LoadScene(“Lobby”);
}

}

Maybe the Scene is not in the Level Index? Check the build settings.