I have been mistakenly charged by Apple I want to know why?

This is a user-to-user support forum. No one here has access to information about your charges but the following may help. If the only indication of the charges is from an email or text, be aware that it may be a phishing attempt to get you to log in to a site that appears to be Apple and divulge your password or credit card information. Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams - Apple Support

You can use the following to determine if it is a real charge, what it is for, and to report a problem: Get help with an item purchased from the App Store, iTunes Store, or iBooks Store - Apple Support

Also see: If you see 'itunes.com/bill' or an unfamiliar charge on your bank, credit card, or debit statement - Apple Support

If necessary, contact iTunes Support. Scroll to the bottom of the page in the 2nd link.

iTunes Support

iTunes Support – world wide