If you’re thinking of cancelling your free trial of CBS All Access on your Firestick, here’s how to do it. First, open the CBS App on your Firestick. Then, go to “My Account” and select “Cancel Subscription.” You’ll be asked to confirm your decision. If you’ve already cancelled your subscription, you won’t be able to reactivate it. However, you can always sign up for a new trial if you decide later that you want to keep the service. ..