If you have noticed an expiration message on your site, that means your Premium subscription was not able to be renewed. This may be due to a number of reasons, including an expired payment method.
To ensure that you keep your site and services active, click the Billing tab under Settings on your Dashboard.
On the Billing Information page you can review your payment method on the Subscriptions panel. To renew right away, click Renew from the Subscriptions panel and enter your new payment method. This will be stored for succeeding transactions.
Once payment is successful, your expiration banner is removed.
I just want to downgrade to a free site.
If you decide that you want to keep your site but do not wish to retain Premium services, you can click the Help menu at the top of your account to email Support. An agent will assist you with cancelling your Premium services.
NOTE: You will be required to remove features that are associated with your premium package. These features include premium templates, enhancements to the webstore, builder, etc before your premium subscription can be canceled.