How do I cancel my subscription billed through Apple iTunes?
You can cancel your subscription (including free trials) at any time. Subscriptions are automatically billed according to the period stated upon purchase (weekly/monthly/annually). The cancellation steps vary depending on how you signed up or who your subscription is billed through.
If you signed up using an Apple device, your subscription is billed and managed through iTunes. You may refer to the video below for the steps on how to cancel your subscription using a computer.