To update your credit card:
1. Log into your account.
2. Click on your name on the top right corner of the screen and click View Profile.
3. Click Billing from the top menu under your name.
4. Click Change Card and update your details.
Note: If receiving an "Oops there was an issue", double check the CVV. For some credit cards (like AMEX) its 4 digits and for other cards its 3.