entity interpolation problems

I read a lot about entity interpolation but I failed to implement it correctly. I am using Photon and that is the code:

     void OnPhotonSarialezedView(PhotonStream stream, PhotonMessageInfo messageInfo)
     {
         if (stream.isWriting)
         {
             State state;
             state.position = rigidBody.position;
             state.timeStamp = (float)messageInfo.timestamp;
             stream.SendNext(state);
         }
         else
         {
             if(states.Count<=20)
                 states.Add((State)stream.ReceiveNext());
             if(states.Count >= 20)
             {
                 var startPos = states[0].position;
                 var endPos = states[1].position;
                 var timeInterval = states[1].timeStamp - states[0].timeStamp;
                 states.RemoveAt(0);
                 gameObject.transform.position = Vector2.Lerp(startPos, endPos, timeInterval);
             }
         }
     }