Apple Pay fails in the App Store and iTunes but works at 3rd Party Vendor Sites… Why?
I looked long and far for this answer and found the blogs did not have a fix for this, nor did the credit card and Apple customer service reps (at least no less than 10 reps over countless hours and days)
One astute Apple rep finally figured it out - the problem was not with the CC on file in Settings under the Wallet & Apple Pay area, but with the CC listed under my overall iCloud / Apple ID area at the very top of settings. Those two sections do not link behind the scenes, so when you’re CC and billing information updates in the Wallet, it does not cascade to the iCloud / Apple ID section.
This was especially difficult to resolve as the problem first shown itself on a linked family member’s phone. While representatives were looking in the wrong place, the astute Apple representative assessed, if you fix the priority account holder’s phone regarding the root payment method in the iCloud / Apple ID area, the update would fix the problem and cascade to the other member phones on the account. That is precisely what happened.
Per this employee, this is a know problem and Apple is working on a fix. Until then, if all other Apple recommendations don’t work for you, you may want to look here.
Lastly, a little side note learned in all of this is that the electronic wallet and Apple Pay are in actuality different elements. While the Apple Pay mechanism did not work on my family member’s phone due to an expired payment method on file, the electronic wallet still functioned fine because the payment method there was active and valid.
iPhone 14, iOS 17