I've just taken over this project and the last developer had implemented cubecart so I wasnt sure where exactly this error was in the stack.
Ok I'll look into the payment gateway.
Couple of quick questions that would help me immensely.
1. Is there an easy way I can tell what the page is to admin login to cubecart, my cubecart is installed in this sort of location -- example.com/shop
2. So just to confirm CubeCart itself doesn't have any methods within it to block access based on an IP allowlist?