Cancel an App subscription if no such option, i.e., no "Cancel" button exists on any device

Hello, maybe you can help me out. How is it possible to cancel an App subscription if no such option, i.e., no "Cancel" button exists on any of my devices (macbook, iPad, iPhone)? I had no intention of renewal of the App and still got it billed for another whole year anyway. I've tried to watch every existing tutorial but normally the get a big reg button with "Cancel" on the bottom of the subscription. No such thing exists for me in any of the current subscriptions and I'm afraid the same auto-renewal will happen with the upcoming expiration dates.