Hi,
We're currently experiencing a problem where our client is receiving a transaction ID that does not exist in the receipt that it received.
One case where this is easily reproduced is by attempting to purchase an auto-renewing subscription that the account is already subscribed to. The client displays the 'You are already subscribed' dialog from the OS, and immediately receives a SKPaymentTransactionStatePurchased from the IAP delegate. Our client then submits both the transaction ID and receipt from this to our server for verification. To verify, we find the specified transaction in the receipt as per the normal server verification process, except in this case, the transaction ID doesn't exist in the 'in-app' section of the receipt (or anywhere else that I can find).
What does this transaction mean and what are we expected to do with it? Is there some way for the client to distinguish this from an actual purchase transaction and ignore it?
This is similar to an existing post here from some time ago, which has no apparent resolution: forums.developer.apple.com/message/228066#228066
Note that this is in the sandbox environment - no idea if this also happens live since we haven't gone live yet.
We're also seeing this problem in some cases where an 'upgrade' to another SKU on the same subscription is processed, but we're currently unable to reproduce that reliably. The 'already subscribed' problem happens every time.
Thanks,
-- Brett