Items bought through our games (in-app purchases) are generally non-refundable. In some cases there can be exceptions. As transactions are controlled by Apple /Google (for Android devices) etc, you should contact them directly to request the way to do so.
Below you will find links to their support pages:

For Apple (iOS) devices:
[Assistance iTunes](http://www.apple.com/support/itunes/)

For Google (Android) devices:
[Google Wallet Support](https://support.google.com/wallet/)

For Amazon / Kindle devices:
[Amazon Support](https://www.amazon.com/gp/help/customer/display.html)

For Facebook payments:
[Facebook Support](https://www.facebook.com/help/)