private void SaveSalesAmount(string scheduleId)
 {
     try
     {
         string routeId            = ScheduleRepo.GetRouteId(scheduleId);
         int    ticketPrice        = RouteRepo.GetFare(routeId);
         int    currentSalesAmount = SalesRepo.CurrentSalesAmount(MainControl.cashierId);
         if (currentSalesAmount == 0)
         {
             int amount = ticketPrice * MainControl.selectedSeatCount;
             SalesRepo.Insert(MainControl.cashierId, amount);
         }
         else
         {
             int updatedAmount = currentSalesAmount + (ticketPrice * MainControl.selectedSeatCount);
             SalesRepo.Update(MainControl.cashierId, updatedAmount);
         }
     }catch (Exception e)
     {
         MessageBox.Show("Error!" + e.Message);
     }
 }