Order issue - error in checkout – Culver's Review

I put order information in. When I click for payment part in checkout, it gives an error. It seems to do with cod sandwich basket when by it self. If I add another item with it, or replace it with a different item, it works. And then if I try to get it by itself again, it will error again.
Review by eachnicknameIwantistaken on Culver's.