All billing on the App Store is handled by Apple directly.

If you require assistance to refund a purchase you made, please get in touch with the Apple Support.

Alternatively, you can request a refund from your device:

•  Log into your device with your Apple ID.
•  Go to Account Settings.
•  Choose Purchase History.
•  Locate your purchase and choose Report A Problem.

This will start the refund process.

Let us know if you have any other questions!