Where do you see the charge?
If it on your bank statement, activity, billing, etc; you need to call the customer
service number on the back of your card or the financial companies to ask questions regarding the charge & to dispute it if it’s not from you or your Apple ID. then change your Apple ID password & financial services password as well.
If you see it in the Apple store purchase/ activity;
Go to settings on your iPhone or iPad, click on your. Tap to view your Apple ID. Scroll down to "Purchase History.” Select the purchase you want to dispute.
Or you can go to the "Report a
Problem" page directly and log in with your Apple ID.
In either event make sure you change your password for both Apple & financial institution.