Hi,
If you are asked to confirm your billing information, make sure that you have a valid card on file, no unpaid balances, and no active subscriptions that have been unable to renew.
https://support.apple.com/en-us/HT207165
Managing Payments
Settings > Name > Media & Purchases > view account > manage payments
*if you see failed or verify in red, your card was recently declined for a purchase, an unpaid balance, or its now expired. Update the payment method accordingly. If the card is valid, has funds available, and the billing address associated to it is correct; click on the card > enter the CVV code > tap done
https://support.apple.com/en-us/HT201266
Unpaid Balances
Settings > Name > Media & Purchases > view account > purchase history
Unpaid balances will show first, and show as pending. To resolve this billing issue, update your card information referenced above.
https://support.apple.com/en-us/HT203005
Subscriptions
Settings > Name > subscriptions
Here you will see all subscriptions associated to your Apple ID, active and inactive.
If you see one that has been set up that is not supposed to be, tap on the subscription > cancel subscription > confirm cancellation.
If the billing issue was associated to this, now that the subscription is cancelled, the billing issue is resolved.
https://support.apple.com/en-us/HT202039
Hope this helps!