I have a customized shopping cart which is using an old integration method to submit cart. In that form I send all items in cart one by one and also send buyers address. Upload is set to 1 and cmd is set to _cart. However, in this method customer's address is not showing in Paypal and this is causing disputes. Paypal has recommended to use smart buttons but my understanding is that it can only be used when your buyer want to buy a single item. In my case they can add multiple products from my catalog and then can pay all of them in one go. Can smart buttons be used for this scenario and if yes how?
Below is code snippet from my existing integration.