Hello, I'm in need of some help. I've recently taken on a new client with a zencart site on an older version (139h). They have had everything working until a week a go in which there have been no changes. The problem is that after paying through paypoint it redirects the user to various error messages and complications such as back to the checkout screen with "Credit card not accepted" or customers have reported multiple charges (this could be them re doing the process because of the false error as it seems to take the payment and send the email fine).

Basically the first problem I need to resolve is why it is redirected them to a failed payment screen.

any ideas?