I would like to add an Apple Card to my Apple Cash card? It is not working. How do I go about doing it without it going for a payment on my account?

How to set up Apple Cash

1. Open the Settings app on your iPhone or iPad.
2. Scroll down and tap Wallet & Apple Pay.
3. Turn Apple Cash on.
4. Under Payment Cards, tap Apple Cash.
5. Tap Continue, then follow the instructions on your screen.

Set up Apple Cash - Apple Support (IN)

Open the Wallet app and tap the Add button . · Select Apple Card, then tap Continue. · Complete your application. · Review and agree to the Apple 

How to apply for Apple Card