We're currently experiencing "InvalidReceiptData" 21002 errors when validating receipts via PlayFab for Sandbox purchases. This started yesterday.
Failed to validate user purchase: /Client/ValidateIOSReceipt: iTunes Sandbox validation result: 21002 (InvalidReceiptData) from https://sandbox.itunes.apple.com/verifyReceipt
This coincides with an App Store receipt signing certificate change: https://developer.apple.com/news/?id=ytb7qj0x and an outage on the App Store Receipt Verification service: https://developer.apple.com/system-status/
I'm looking for some confirmation as to whether or not this is something we need to sit and wait for Apple to resolve, if it's an issue PlayFab need to investigate, or if there's anything developer-side we can do to mitigate this.