public IActionResult Login(CustomerViewModel customer)
        {
            // verify login
            if (customerViewModel.Login(customer.Name) is null)
            {
                customer.Name = null;
            }

            ModelState.Remove("CustomerSelected");
            if (ModelState.IsValid)
            {
                TempData["CustomerLoggedIn"] = customer.Name;
                TempData.Keep("CustomerLoggedIn");
                return(Redirect("/Customer"));
            }
            return(View());
        }