public async Task <ActionResult <List <Bill> > > Post( [FromServices] DataContext context, [FromBody] Pdv model) { BillRepository billRepository = new BillRepository(context); decimal change = model.AmountPaid - model.Price; //Change limit if (change >= 10000) { return(null); } context.Pdvs.Add(model); List <Bill> lBills = billRepository.CalculateChange(model); //context.Bills.UpdateRange(lBills); context.SaveChanges(); return(lBills); }