Cancel on a computer
Sign in to my.roku.com and go to My subscriptions.
Under Active subscriptions, select the subscription you want to cancel.
Select Manage subscription and then select Turn off auto-renew. Turning off auto-renew means you've canceled your subscription and you will not be billed for it in the future.
After canceling your subscription, you'll continue to have access to it until the end of your current billing cycle.