How do I request a refund through the Apple App Store?

To request a refund please contact Apple support from here: https://www.apple.com/support/contact/.

Then follow the steps below:

1. Tap on Billings & Subscriptions
2. Tap on Request a Refund
3. Tap on Continue
4. Tap on Get Started
5. Complete the form and choose the Balance purchase from the list
6. Tap on Submit

For international contact information, go to this website.