public void SelectSeat(int userId, int seatNumber) { //create document model var planeSeatsArrangement = new Models.PlaneSeatsArrangement() { SeatNumber = seatNumber, UserId = userId }; allSeats.Add(planeSeatsArrangement); var returnData = Newtonsoft.Json.JsonConvert.SerializeObject(planeSeatsArrangement); Clients.All.selectSeat(returnData); }