I need to know what iTunes is charging monthly

See instructions in See or cancel your subscriptions - Apple Support

If there is a charge not shown there, another possibility is that it is for an upgrade from the free 5GB iCloud storage plan. To see what plan you are on and to downgrade if desired, see: Downgrade your iCloud storage - Apple Support

If the above doesn't resolve the issue, see the following instructions. They include information on contacting Apple Support if the other steps don't help: If you see "apple.com/bill" or an unfamiliar charge on your statement - Apple Support

Click here and follow the instructions.

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