If the subscription that you want to cancel is an iCloud storage plan
If the subscription isn't billed through Apple
Don't see the subscription when you follow the steps to cancel your subscription? You might have purchased that subscription from another company.
On your bank statement, find the charge for the subscription. If your bank statement doesn't say Apple, apple.com/bill, or something similar, Apple doesn't provide this subscription to you. To cancel the subscription, contact the company that offers the subscription to you. Statements often list the name of the company, such as Hulu, Pandora, YouTube, Amazon, HBO, etc.
If you have more than one Apple ID
If a family member signed up for the subscription
You can’t cancel a family member's subscription. Ask your family member to use their own device to cancel the subscription. Or if you share a device, ask that family member to sign in with their Apple ID and cancel the subscription.
If you want kids to get permission before they buy a subscription, turn on Ask to Buy.
If you want to cancel an AppleCare plan
Contact Apple Support
If you still can't find the subscription and cancel it, contact Apple Support.