You can make a refund for unused items by contacting Apple or Google for a refund. Policies and conditions for refunds may vary from shop to shop. You can check by following the links below:
Apple: https://support.apple.com/en-us/118223
Google: https://support.google.com/googleplay/answer/2479637?hl=en&sjid=1717878105587762443-AP

* Please note: Unauthorised refunds may be recognised as malicious refunds and result in your account being blocked in accordance with the User Agreement.