What do you see when following the steps here under "See your purchase history on your device"?
View your purchase history for the App Store and other Apple media services - Apple Support
Are you the Organizer of a Family Plan that uses Purchase Sharing? If so, that means members are allowed to make purchases to your payment method. You are still able to view those purchases, but would need to choose their name in the in the Family Plan.
Also, what is the exact description of the charge you are seeing and where are you seeing it, including the "Pending" amount.