I have a profile with managed payload that is Exchange activesync. 40+ devices. I just upgraded all IOS devices from 8's to 12's and 13's. Every profile in the MDM worked just fine except mine. Both the iPhone 8 and 13 will not pull emails. It is setup the same way as the others.
On the profile and the mail app on the iPhone, it shows that it is connected. But emails will not populate. Been banging my head for months now.