It's technically impossible for us to refund payments made via the App Store due to the limited access to the payment information.
We cannot track such transactions because Apple sends the encrypted information to developers to ensure the safety of your sensitive data.
You can learn more about Apple security rules in this article: https://support.apple.com/en-us/HT203027.
Please contact Apple Support directly: https://support.apple.com/
Tips on how to avoid accidental purchases:
https://support.apple.com/en-us/HT204396
Here are the articles with some tips to prevent Underage Purchases in the future:
- Ask to Buy
- Screen Time Settings
Please check that Purchase Restrictions are set up on your devices (Settings -> General -> Restrictions) to avoid unauthorized payments.