I have the same issue. I think it's a known issue, as people on Feedback Hub have the same problem. Guess we have to wait for a fix overall. Interesting enough, if you go to NFC area in the settings it still references your Cards. Rather strange.
It would appear that MS is working on this issue. I got an update for the wallet app today. The option to add a payment card is back but trying to add a card results in an error screen. So some good news and some bad. I hope they get this sorted soon