Why do I need a default payment method
Manage or replace your saved payment information for your CE Zoom subscriptions.
Note About Keeping Payment Methods Current
Pro and Elite Members:
If you are on the Pro or Elite Plan, and you see this message please make sure your payment method is updated to avoid any service interruptions or accidental membership cancellations. Failure to update may also result in the loss of your grandfathered pricing.
Basic Members:
If you see the red warning message but are not currently on a Pro or Elite plan, you can ignore it.
If you are on the Basic or Free Plan and want to clear the message, click the downgrade button under the Basic plan to reset your account.
During this process, the system may prompt you to add a default payment method, but your balance will show $0.00 and you are not required to save a payment method for the Basic plan.

This warning is only relevant if you are subscribed to a paid plan.