If you would like to cancel your website subscription to a paid plan and be downgraded to the Free plan, follow the steps listed below.
How-to
First, visit the "Billing" page in the "Settings" section in the Admin Portal. Here, under the renewal date box, click the red "Cancel subscription" button.
On the next page, fill out the prompts and click the red "Cancel subscription" button.
Once you've canceled your subscription, and after any remaining time your community has paid for runs out, your community's website will be downgraded to the Free plan.
You will always be able to re-subscribe to a paid plan at any time by visiting the "Billing" page in the "Settings" section of the Admin Portal. Here, an informational notice will appear with a link to resubscribe. On the next page, enter your payment information.