How do you change your Apple Music subscription credit card?

Check out this article from Apple for more information on how to change the payment method for your Apple services...

https://support.apple.com/en-us/HT201266

From your iPhone or iPad go into Settings ⇨ click on iTunes App Stores ⇨click on Apple ID ⇨ View Apple ID ⇨ Manage Payments ⇨ under Found in Wallet choose a card that is already in your wallet OR under Payment Method choose: Apple Card, Credit/Debit Card, or Pay Pal.