Only account owners can update the payment information on an account
When entering your credit card information, be sure to re-type everything (name, address, payment information). Do not use the auto-fill feature.
If updating your billing address, you'll need to re-enter your credit card information as well
You can only have one form of payment for all service lines on the account. If you would like to have a separate payment, you will need a separate account for your service line.