Hi @BillH1 ,
More often than not, isolated incidents of a customer’s card being rejected at checkout are due to an issue on their bank’s end rather than the gateway itself. However, if you’re seeing numerous instances of cards being declined, it’s worth checking your abandoned checkouts to see if any reasons are given for the failed transactions. Payment events for the abandoned checkout often give you an idea of why the payment failed.
If you’re still unsure of why this is happening, please feel free to contact our support team directly so that they can authenticate you on your store and take a closer look at this for you.