Countdown photon

I did this script and it works fine but there is a problem, when I enter room it works fine and countdown works, but when someone else enters the room it counts down again, I want when a player enters, the camera is placed on the player who was already in the room.
sorry for my english

Code (CSharp):

1.    private Text TimeUIText;
2.     private float timeToStartRace = 5.0f;
3.     private void Awake()
4.     {
5.         TimeUIText = DeathMatchGameController.instance.TimeUIText;
6.     }
7.     // Start is called before the first frame update
8.     void Start()
9.     {
10.     }
11.     // Update is called once per frame
12.     void Update()
13.     {
14.         if (PhotonNetwork.IsMasterClient)
15.         {
16.             if (timeToStartRace >= 0.0f)
17.             {
18.                 timeToStartRace -= Time.deltaTime;
19.                 photonView.RPC("SetTime", RpcTarget.AllBuffered, timeToStartRace);
20.             }
21.             else if (timeToStartRace < 0.0f)
22.             {
23.                 photonView.RPC("StartTheRace", RpcTarget.AllBuffered);
24.             }
25.         }
26.     }
27.     [PunRPC]
28.     public void SetTime(float time)
29.     {
30.         if (time > 0.0f)
31.         {
32.             TimeUIText.text = time.ToString("F0");
33.         }
34.         else
35.         {
36.             //The countdown is over
37.             TimeUIText.text = "";
38.         }
39.     }
40.     [PunRPC]
41.     public void StartTheRace()
42.     {
43.         GetComponent<CarUserControl>().enabled = true;
44.         this.enabled = false;
45.     }

 

Any help please