I want to cancel my Apple TV subscription but the option to cancel does not appear on my I phone or my Mac

If you see the Apple TV subscription listed as one of your subscriptions, but it doesn’t have a Cancel option, but instead resubscribe options, then it is already canceled.

A subscription that is already canceled, will also have another change: instead of a next billing date, it will list the expire date.

Canceled subscriptions may stay active until the expire date (end of the billing cycle).

See or cancel your subscriptions - Apple Support

If the subscription is not listed for the signed-in account, then possibly the subscription is for a different account?

When did you originally sign up for the subscription service?