public async Task <string> CancelReservation(Guid id) { try { var filter = Builders <Reservation> .Filter.Eq("Id", id); var reservation = _reservation.Find(filter).FirstOrDefault(); if (reservation == null) { throw new Exception("Book doesn't existst"); } var newTransferReservation = new CancelReservation() { RoomId = reservation.RoomId }; await _publicher.CancelPublish(newTransferReservation); _reservation.DeleteOne(Builders <Reservation> .Filter.Eq("Id", id)); return("Reservation was canceled successfully"); } catch (Exception ex) { throw ex; } }