Unable to detect error while using PhotonView.isMine method

while using below mentioned code this error appears “PhotonView does not contain a definition for ‘isMine’ and no accessible extension method ‘isMine’ accepting a first argument of type ‘PhotonView’ could be found (are you missing a using directive or an assembly reference?)”

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using Photon.Pun;
 using Photon.Realtime;
 using System.IO;
 using UnityEngine.UI;
 public class PhotonPlayerSetup : MonoBehaviourPunCallbacks, IInRoomCallbacks
{
private PhotonView PV;
void Awake()
{
    PV = GetComponent<PhotonView>();
}
void Start()
{
    if(PV.isMine)
    {

    }
}
}

Are you using PUN2? In that case you need a capital I instead of a lower i. So IsMine instead of isMine.