Only Google Play refunds are supported, and only on the contingency that the old order can be refunded, which may not be possible for old orders. Amazon app store purchases can not refunded, I suggest you contact Amazon App store support.
If the app is not working for you, we will issue refunds up to 72 hours after purchase. Have you previously requested a refund by email, we will use the date of that mail as the refund date. If your refund request doesn't fall in the 72 hour window it will be rejected.
Please provide order id from google Play or we will not be able to refund order.