how to cancel an iTunes subscription

Did you already follow the steps explained in this article to do that?

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Cancel a subscription on your Mac

1. Open the App Store app.
2. Click the sign-in button  or your name at the bottom of the sidebar.
3. Click View Information at the top of the window. You might be asked to sign in.
4. On the page that appears, scroll until you see Subscriptions, then click Manage.

5 . Click Edit next to the subscription that you want. Don't see the subscription that you're looking for?

6 . Click Cancel Subscription. If you don’t see Cancel Subscription, then the subscription is already canceled and won't renew. 

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copied from: How to cancel a subscription from Apple - Apple Support

Click here and downgrade to the free 5GB. If you can't find it, use the link to contact Apple Support.

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