We are sorry to see your user leaving, but we know sometimes it happens. Users can cancel a subscription on their own by following these instructions or you can help them as an admin.
NOTE: If the subscription originated through an app purchase, the user must cancel through the app used to purchase that subscription. Canceling an in-app purchase via the web UI will not cancel their app-based subscription. An admin cannot cancel this for a user.
Navigate to the People tab, and under the second People tab, find the user you want to cancel the subscription for and click Edit. Under the Access section, go to the active subscription (highlighted in green), click on the 3 vertical dots (⋮), and select Cancel.
NOTE: By selecting Cancel, the user will have access until the end of the paid billing period. If you choose Delete, their access will be removed right away.
When an admin manually cancels a subscription for a user, an email notification is sent to the user regarding the cancelation, if you have this email enabled in your Email Templates.