Hello everyone who develops Merchello!

Guys, thank You for the free ecommerce module, but don't You think that You have too many errors?

Today I upgraded to the latest version 1.6.1, but important problems were not solved.

Below I will try to describe my problem:

1. I have the following settings

2. Two products

*The second product has the same settings but a different article

3. Create invoice

4. "Capture funds" goes well.

5. But when I click on "fulfill' I get the following error

I really need Your help to understand what I'm doing wrong.

Below is my code for the functionality of checkout.

public ActionResult Checkout(CheckoutModel model)
        {
            if (ModelState.IsValid)
            {
                var address = new Address
                {
                    Email = model.Email,
                    Name = model.Name,
                    Phone = model.Phone,
                    Locality = model.City,
                    Address1 = model.Address,
                    PostalCode = model.PostCode
                };

                

                Basket.SalePreparation().SaveBillToAddress(address);
                Basket.SalePreparation().SaveShipToAddress(address);

                var paymentMethod = MerchelloContext.Current.Gateways.Payment.GetPaymentGatewayMethods().First().PaymentMethod;

                var preparation = Basket.SalePreparation();

                preparation.SavePaymentMethod(paymentMethod);

                if (!preparation.IsReadyToInvoice()) return RedirectToUmbracoPage(BasketPageId);

                IPaymentResult attempt = preparation.AuthorizePayment(paymentMethod.Key);

                if (!attempt.Payment.Success)
                {

                }
                else
                {
                    Notification.Trigger("OrderConfirmation", attempt, new[] { preparation.GetBillToAddress().Email });
                }

                return Content("Complete");
            }
            return RedirectToUmbracoPage(15298);
        }

Thanks!