Apple Gift Card balance not working for in-game purchases

I bought and used an apple giftcard and I could buy stuff for like an hour then when I tried to purchase something in-game it says “unable to purchase check this check that” and nothing helps because it’s talking about adding a new or changing the payment method. I don’t want to use my cards, just the giftcard but I can’t buy anything and I have enough to buy what I want

[Re-Titled by Moderator]

Original Title: Apple balance