Need help with my payment method

Either contact your carrier, or change your payment method : Change, add, or remove Apple ID payment methods - Apple Support

You cannot remove all payment methods if you have any active subscription on the account, including iCloud storage

If necessary, contact iTunes Support. Either use the form or scroll to the bottom of the page in the 2nd link. Follow through the screens to get a chat or telephone option.  You may need to pick a problem that is slightly different than yours to get a chat option.  

iTunes Support

iTunes Support – world wide