We are still getting reports of this from our users and still no feedback from Apple's Feedback Assistant.

We have not found a resolution to this issue yet, nor have we had any response or support from Apple. We have many users a day writing in to our Customer Service team saying they are being charged for the IAP yet they are receiving this 21107 error and no receipt is ever returned to us so redemption of the purchase is impossible. This has become very frustrating for us and our users so if anyone has any information about what might be happening here I'm willing to try anything at this point. We've even resorted to start recreating all of our IAP codes in the slight chance that it may help.

Thank you for your reply. I have filed a ticket with the feedback assistant as you suggested. Ticket FB13615473. You requested attaching sysdiagnose, but I didn't make it clear in the original post that we have been unable to reproduce this issue internally. We have numerous users that have been contacting our Customer Support team, all with this same 21107 error. Any support that we can get is appreciated.

We are having the same issue. Submitted a build on Tuesday January 12th that went thru with no problems. Build that was submitted tonight now has the same rejection. Dear Developer, We identified one or more issues with a recent delivery for your app, "xxxxx". Please correct the following issues, then upload again.  ITMS-90000: This bundle is invalid - $message.  Best regards, The App Store Team The changes were minimal and the build process was exactly the same. The fact that nothing really changed on our end and there is $message in the email instead a valid response makes me feel like there is something going wrong on Apple's end, or some part of the process changed just today. If anyone has any other information or guesses to what it might be it's appreciated.