You cannot request a refund in this user-to-user forum. The Apple Recommended post has a link with instructions on how to request a refund, among other information. But you have to understand that there is no such thing as an unauthorized purchase, so you need to figure out why you were charged in addition to requesting the refund, or you will just be charged again. If you were charged by Apple for something there are a few possibilities:
The bottom line is that Apple never charges you for any purchase without authorization. So someone with access to your account must have made the purchase or subscription, if it wasn’t a scam message.
If it is a specific item on your bank or credit card statement see this link ➡️ If you see "apple.com/bill" or an unfamiliar charge on your statement - Apple Support
You can review all of your purchases as described in this link ➡️ See your purchase history for the App Store or iTunes Store - Apple Support
If it is a subscription you can cancel it here ➡️ See or cancel your subscriptions - Apple Support.
Note that subscriptions are not canceled when you delete an app; the subscription must be canceled separately from deleting the app.
And you can request a refund here ➡️ Request a refund for apps or content that you bought from Apple - Apple Support