I’ve been in touch with apple support and they can’t find the subscription either however I have been billed monthly since 2020
. . . but don’t know how if myself or Apple can’t find the subscription.
A question: did you purchase the Disney Plus subscription directly from Disney Plus or via Apple?
Check your mail box, look for the last invoice where you paid for Disney Plus subscription.
Is the invoice from Disney Plus or from Apple?
If you purchased the Disney Plus subscription directly from Disney Plus, you must cancel at Disney Plus.
Based on Disney Plus, you can cancel at any time, effective at the end of the billing period.
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Check for sure the following Apple articles:
View your purchase history for the App Store, iTunes Store, and other Apple media services
View your purchase history for the App Store, iTunes Store, and other Apple media services - Apple Support
How apps, content, and subscriptions from Apple are billed
How apps, content, and subscriptions from Apple are billed - Apple Support
If you see "apple.com/bill" on your billing statement
If you see "apple.com/bill" on your billing statement – Apple Support (UK)