Apple Card failing to work for Apple purchases

My Apple Card keeps failing when I try to check out with Apple. I've tried using the card directly twice and then tried using Apple Pay with the card loaded. I dont see card numbers on the physical card so I can't try to buy directly using that. I double checked there is plenty of available credit in the Wallet app. It feels dumb to not get the cash back on my card given that this is an Apple purchase.

Any thoughts on why this would fail?