public void OnRoomLeft(RoomParticipatedDTO roomParticipatedDTO) { if (_httpToken.UserId == roomParticipatedDTO.UserId.ToString()) { var room = MyRooms.Where(r => r.Id == roomParticipatedDTO.RoomId).FirstOrDefault(); ChangeData(delegate { OtherRooms.Add(room); MyRooms.Remove(room); Messages.Clear(); }); } }