Unusual charges

See if you can access your purchase history to find out what it is. If you need further answers then please contact apple directly. These forums are just user to user so no one here can access the info you need

View your purchase history for the App Store, iTunes Store, and other Apple media services - Apple Support

...appears on my bank statement but not on my Apple transaction history

That suggests it is fraudulent charge, likely due to someone have gained access to your card number. Notify you bank and/or card issuer immediately.

If Apple has no record of the purchase, they cannot help. You financial institution can.