To update the credit card on your account go to the Press8 Control Panel at: https://manage.press8.com, enter your username & password (your username is usually your email address, and if you have forgotten your password click on 'Lost Password')
*** Note: Only Administrators can update the payment method.
Then click on: Settings=>Payment
and update your credit card information.
Then click 'Save'.
Charges on updated credit cards will be processed that night at midnight.