i need to cancel apple tv that i had through t mobile

Apple TV+ On Us - FAQ - T-Mobile (US)

Can I cancel Apple TV+ at any time?

Yes, you can cancel your Apple TV+ subscription through T-Mobile anytime. T-Mobile customers can cancel their subscription through the T-Mobile app or online at my.t-mobile.com by removing the Apple TV+ feature.

If you subscribed to Apple TV+ prior to receiving this promotion through T-Mobile, check your profile settings to see if you need to cancel with Apple as well.

Sprint & T-Mobile for Business customers can cancel their subscription through Apple.