If you subscribed in our app on iPhone or iPad and made the purchase using your Apple ID, you need to request the resolution through their means. We as developers do not have any means to perform refunds for iOS transactions as the billing system is fully regulated by Apple and all the payments are processed on their side. That's why the only way for you to receive a refund is to contact Apple support team.

This manual will help you https://support.apple.com/en-us/HT204084  

Apple Support Portal https://support.apple.com/en-us/HT201232

Please also read their Terms and Conditions: https://www.apple.com/legal/itunes/us/terms.html