Unauthorized subscription

Did you by any chance download a free trial subscription of an app that you simply deleted? Deleting an app, does not cancel the subscription.

View, change, or cancel your subscriptions - Apple Support

Get help with subscriptions not billed through Apple - Apple Support

If the above does not apply, then take a look at the following articles:

If you see 'itunes.com/bill' or an unfamiliar charge on your statement - Apple Support

Request a refund for an App Store or iTunes Store purchase - Apple Support

I have no idea. This is a user-to-user technical support forum. We don't know who you are. We know nothing about your account. How do you know you are being charged? Did you get an email saying so? (Hint: It's most likely a scam to get you to provide personal information). Have you checked your iTunes purchase history as described here-->See your purchase history in the App Store or iTunes Store - Apple Support to see if you were actually charged by Apple, and if so, what it was for? Do you share an Apple ID with anyone who might have charged something? Do you suspect your Apple ID was hacked? If so, see-->If you think your Apple ID has been compromised - Apple Support.

Did you see a charge on your credit/debit card statement?If you see 'itunes.com/bill' or an unfamiliar charge on your statement - Apple Support

I'm really just grasping at straws, because you haven't explained anything about what you think you were charged for.

Hello, try to check on itunes store. Open the app and go down. Press "Account" and over here you can see your card and your purchase history