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.
see: If the subscription that you want to cancel is not listed - Apple Support