Apple gift card for in app purchases
I have a 10 dollar apple gift card and am unable to use it as an in app purchase for the game Mafia City.
iPhone XR, iOS 15
See -> How to redeem your Apple Gift Card or App Store & iTunes gift card
How to redeem your Apple Gift Card or App Store & iTunes gift card – Apple Support (UK)
When redeeming a gift card, the amount will be credited to your (1) Apple ID balance and (2) you need to set your Apple ID balance as your default payment.
1.
See -> Check your Apple ID balance
Check your Apple ID balance – Apple Support (UK)
(2)
Change, add or remove Apple ID payment methods
Change, add or remove Apple ID payment methods – Apple Support (UK)
If you update your payment method or add funds to your Apple ID balance, It would take about 1 to 3 business days in order to process.
If you're still unable to update your payment method, Contact Apple Support.