I got this message from the iTunes Connect: What's it mean and how do I resolve it?
"We have begun the review of your app but aren't able to continue because we can't locate authentication within your app.
At your earliest opportunity, please reply to this message providing the steps for locating authentication in your app.
While your iTunes Connect Application State is displayed as Rejected, it is not necessary to upload a new binary. Once you reply to this message, we can proceed with your review."