We have used Square REST APIs for managing customer cards and processing payments for over a year now, and everything has been mostly problem-free. However, recently we have encountered two episodes:
A customer from Mexico has always been able to pay with a digital debit card, which has a dynamic CVV that changes every couple of hours. It worked fine for a few months (of course the latest CVV is entered each time), but starting about a month ago, the card got declined every time. The error message returned by the API is just some “general auth error”.
A customer from France wants to add their card as a “saved card” (we use the Cards API under Payments API under the hood). However, the Square web form doesn’t recognize his card, which is a standard Visa credit card issued by la Caisse d’Epargne.
Are there any pointers for how we should debug these issues? Thanks so much in advance.