Cash app
apple pay wont let me add my cash app card to it
iPhone SE, iOS 17
Check with the card issuer to see if it's compatible. Not all cards are.
Apple specifically refers to:
To set up Apple Pay, add a debit, credit, or prepaid card to the Wallet app on your iPhone, Apple Watch, or other compatible device.
It's possible that your Cash App card is considered none of those.
Add cards for Apple Pay - Apple Support