I submitted an application for review and I notice that the build that I submitted has an issue associated with it saying that Build 168 does not contain the correct b
I was also facing same issue but suddenly the message in the itunesconnect got changed to "To use TestFlight Beta Testing, this build must contain the correct beta entitlement. For more information, see the(Link)" in the prerelease section.
With TestFlight Beta Testing, you can distribute your prerelease builds to testers to collect feedback and prepare your app for release in the App Store. TestFlight Beta Testing is optional; you can submit your app for review without using it.
Ref: here