Change Credit Card
Only the Account Owner is able to adjust the billing information. If you do not see the Account & settings link in the right hand corner of your account, you're not the Account Owner.
Click the Account & settings link and select Account, upgrades, billing at the bottom of the dropdown.
Now click change card at the top right corner of the page. Enter the new card details on the next screen to update your credit card.

Next article: Manage Invoices
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