In order to update your billing (Credit Card) info in ShufflePoint, simply login to ShufflePoint.com and click on the "Subscription plan & billing" link in the right sidebar....

If you already have a paid plan you will see a link to update your credit card info...

If your plan has changed, you will see a different message for approving this change and either using the credit card on file, or entering a new one...

These links will take you to a form where you can enter or update your credit card information....