Canceling an unauthorized purchase
How do I to to cancel and Manage purchasing and cancel an unauthorized purchase
iPad 2, iOS 9
See your purchase history for the App Store or iTunes Store https://support.apple.com/en-us/HT204088 to make sure the charge are from Apple. And, see If you see apple.com/bill, itunes.com/bill, or an unfamiliar charge on your statement https://support.apple.com/en-us/HT201382
If you have a problem with an alleged subscription or a purchase, see Subscriptions and Purchases https://support.apple.com/en-euro/billing. If you think you have a refund coming, then use the request a refund link. It will take you to Request a refund for apps or content that you bought from Apple https://support.apple.com/en-euro/HT204084
See How long refunds from the App Store or other Apple services take https://support.apple.com/en-us/HT210904
You also may be able to get Apple telephone support for help in solving the problem using this link https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362
And here is how to contact iTunes worldwide support via text or chat using this link https://support.apple.com/choose-country-region/itunes After choosing your country, see the heading Tell us how we can help.
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But, I am concerned that you may have been scammed. Apple does not make many billing errors.
Did you possibly provide any potentially damaging information to anyone? If yes, you'll need to follow up, for example, with a credit card company, Apple, Social Security, your
bank, etc.
If you gave you Apple ID password to a scammer, then
Change your Apple ID password https://support.apple.com/en-us/HT201355
Here is What to do after you change your Apple ID or password https://support.apple.com/en-us/HT204071