public IActionResult ManageBus(BusManageViewModel viewModel) { var bus = mapper.Map <Bus>(viewModel.Bus); bus.BusWorker = busWorkerRepository.Get((long)bus.BusWorkerId); var busWithSelectedWorker = busRepository.GetBusWithWorker(viewModel.Bus.BusWorkerId); if (busWithSelectedWorker != null) { busWithSelectedWorker.BusWorker = null; busRepository.Save(busWithSelectedWorker); } busRepository.Save(bus); return(RedirectToAction("ManageBus", "Bus")); }