iPhone won’t accept my card as a payment method

I was trying to purchase something on an app and then it tried to verify using my card issuer. Even though I went through this process it still denied it so I tried to remove the payment method and add it again. This didn’t work. Now a message appears saying this: “payment method declined, try updating it or adding a new payment method.” And now it won’t let me add my card. I have Googled and tried every method recommended and none work. Everything is registered to the right address of the right country and every other card I tested worked (not mine so I can’t just “use another”) but mine doesn’t on any phone I tried it with. Is this a problem with my bank or what? It’s even stranger because it lets me register it to Apple Pay but not use it as a payment method. What do I do?