How to Update iTunes billing information?

Your Apple ID contains info such as your address, credit card number, country, and ​email address. If you move, change credit cards, or create a change that affects this info, update your ​​Apple ID therefor that it continues to work correctly. How to Update iTunes billing information your Apple device.

iTunes-billed subscribers can update their payment information on iTunes using a computer or an iOS device.

iOS device.

Computer:

Open iTunes
At the top of the computer screen or iTunes window, select Account > View My Account (and sign in)
Select Manage Payments next to Payment Information
Make the necessary edits to your payment method
Click Done to save the changes

iPhone or iPad:

Open the Settings app
Select your name > iTunes & App Stores
Tap your Apple ID > View Apple ID (and sign in, if prompted)
Tap Manage Payments
Add or update your payment method