how do i find out which phone or device my charges are coming from
I’ve got storage upgrade I’m paying for the music and iTunes so and getting double charged
Charges are tied to an Apple ID, not to a specific device that is using that ID. You can use the following instructions for information on how to unsubscribe from something or to downgrade to the free 5GB level of storage:
View, change, or cancel your subscriptions - Apple Support
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