Is there an issue with buying train tickets on bahn.de (specifically on int.bahn.de)? I've tried multiple credit cards, web and app, and logged in and as guest, and it does not accept the credit card. Message is "Means of payment was refused". There's no activity on my credit card, so it's not even getting to that point.

Just curious if anyone has dealt with this and has a solution. I've contacted DB, and awaiting a response.