If you are being asked to enter a payment method, Apple has multiple criteria* requiring the presence of a payment method, even for free items. Since you may be encountering one of those situations, you have no option but to enter a valid payment method if you wish to continue downloading. Read the support article Add a payment method to your Apple ID - Apple Support about how to do that. The payment method may not be charged if you also have account balance or the item is free, but the payment method has to be present. This next article lists valid payment methods for different countries but note that in this situation Apple Account balance alone apparently may not meet the requirement and you need to use another payment method until you find one that satisfies Apple's requirement (often a credit or debit card): Payment methods that you can use with your Apple ID - Apple Support.
Read this document about how to view your current payment types and add Apple ID payment methods on an Apple mobile device, a Mac, or a PC --> Add a payment method to your Apple ID - Apple Support
If an item appears in red then it is no longer working and you either need to replace it or get it working again.
Check this resource about what to do if your payment method is declined in the App Store or iTunes Store. Click here --> If your payment method is declined in the App Store or iTunes Store - Apple Support
- Apple is checking with your financial institution if the payment method is valid and receiving a negative response. Make sure the name and address are entered exactly as it appears on your financial institution bills and that the 3 digit CVV is correct. Check with your financial institution about the status of your card.
- Make sure your payment method is up to date or to try a different one ( If you need to change or update your Apple ID payment method - Apple Support ).
- Make sure this is one of the payment methods that you can use with your account, as listed in this support article: Payment methods that you can use with your Apple ID - Apple Support ) A solution may be to use a method from the same country as the store you are using, but Apple no longer states either way if this is a requirement (it used to say, "Make sure that the billing address for your payment method matches the billing address for your Apple ID" but has now downsized this to "You might need to ask your financial institution to allow international purchases on your debit or credit card." in: If your payment method is declined in the App Store or iTunes Store - Apple Support .
・Unfortunately the list is somewhat general and does not list individual brands of cards (I guess there are too many and are constantly changing).
・Also read any footnotes in the document.
・Finally, note that the document only says which methods _are_ acceptable. Apparently certain types (usually a credit or debit card) _must_ also be present under certain situations such as when a subscription is involved.
If you still have problems, contact official Apple Support. Click here --> Choose your country or region - Official Apple Support Select your country, then a product. If you don't see one that handles your issue then keep experimenting with selections until you reach one that gets you a chat session or a telephone call and get the representative to redirect you.
or:
See a list of Apple phone numbers around the world, in this article --> Contact Apple for support and service - Apple Support
If you're in India, click on this link to read an April 2022 notice 'About billing for Apple subscriptions and media products in India' --> About billing for Apple subscriptions and media products in India - Apple Support
Additional verification that may be required when making purchases in Europe --> About billing and purchases in Europe - Apple Support