I've been getting a few more of these recently. I receive payment but the player does not receive their coins. When I look at the transaction in the payvault it says "Invalid IPN postback from PayPal: Could not verify request at PayPal, result=". And that's it. Usually the player just contacts me, I check it out, and give them their coins. But it still seems like bad business when it happens.
Is there any way to stop or reduce this, or is it something on paypals end? Any details on what it is?