Hi, I sell only one service on my site, and I enabled express checkout so that when customers click purchase, it directs them immediately to the checkout page.
My problem is this - if the customer clicks back or decides to abandon the checkout, and later returns to purchase, they cannot click on the purchase button again - a message that says "UNABLE TO PURCHASE ITEM. Sorry, we only have 1 of that item available." pops up. I figure that the problem is because I listed my products as a service, and the item stays in the cart when the customer first clicked on purchase. When they click on purchase again, squarespace is trying to add the same product into the cart again, thus the error message pops up.
Now since I only have one type of service and the concept of cart doesn't quite apply (hence express checkout is enabled), how can I clear the cart always so that this problem doesn't occur?