Follow these steps to cancel the entire subscription, including the Pro add-on (if only canceling the add-on, different instructions are further down the page):
1. Log into your Frase account.
2. Click Account --> Subscription and press "Cancel Full Subscription" in the view that appears. If the subscription is terminated on the Team plan, then users on the Team will have access to their own docs only and not other team members' documents.
To disable the add-on only, click "Cancel Add-on only" as shown in the screenshot below. Your subscription will stay, but the add-on will be canceled.