iPhone X stopped syncing mails and contacts after iOS 12.3.1 Update

Question

Hello Sophos Community, 
 
 our CEO managed to upgrade his iPhone X to the newest iOS Version (12.3.1)&hellip; since then, he is not receiving emails and cannot send mails aswell.. later that day he recognized that contacts Arent syncing aswell&hellip; 
 He had the version 12.2 before and everything was working fine. 
 I already tried to de-Register and enroll the device completely new, but that didnt help&hellip; now he has 0 Mails or contacs on his iPhone because the sync is not working. 
 I was already looking for a iOS Downgrade, but our lovely Company Apple already stopped signing iOS 12.2 and earlier. 
 
 Our SMC-Server is running 9.0.2 and we already disable HTTP/2 on the last update... 
 
 Hope you have a Workaround for me, our CEO really Needs his Phone/Mail/Contacs next Week on his Business trip to the US... 
 
 Thank you in Advance! 
 Regards

ADPAT · Answer

So... 
 
 I managed to get it working somehow. The Problem was, that i needed to add the Password manually in the accountproperties of the iPhone and then i restarted the phone completely, after that it startet to sync everything&hellip; 
 Actually dont know what that was but seems to be working&hellip; I will test that further with my iPhone to see if i can recreate that issue. 
 
 Thank you anyways. 
 Regards