Apple Wallet will not allow me to add ANY cards

I experienced the same issue when I upgraded my phone this week.I had three separate cards from different banks but was experiencing the same issue with them all. I have tried every possible solution with apple such as restoring my phone twice and running diagnostics. I was on the phone yesterday for 7 hours between 13 different people from Apple (as they kept hanging up) , 3 from visa and 2 from my bank and nobody could help me. I eventually figured out myself that the issue was my icloud. My brother accidentally set our family icloud to his age which is 15.For this reason when I tried to add my cards to my new phone or add them back to my old phone it will no longer allow me to use apple pay due to the age restriction. But when I used a different icloud, I experienced no issues. Apple did try to argue it was not their issue but I found it odd that none of my cards would work when they were from different banks

It’s not the phone. One of the issuing banks or the Payment Network Operator (PNO) is blocking a card. When you attempt to add other cards those banks are notified of the block from the other bank. It is a bank issue.

Probably the bank that issued the first card block it (could be multiple issues) then that block stopped the other three. The more times you attempted to add cards, the more your attempts looked fraudulent to the banks.

Are you getting to the step where you agree to the terms & conditions?

Unfortunately, yes. Also, stop attempting to add the cards. Each time an attempt is made, it looks more like fraud from the banks and PNO perspective.

So, happy to hear you were able to resolve your issue. I hope you have a great weekend!