Activesync on outlook weird times

I am having a weird problem I have activesync setup on my phone and my outlook 2016 but when some emails come in my phone will show the time they came in no problem but my outlook will have them at 12am for when they came. Most of the time this happens for a little while after I have restarted the server. Any ideas why it would do this I have the latest miab installed.

Thank you

Z-PUSH (Used for activesync AFAIK) has known issues with Outlook 2016:

For Outlook on Desktop I would use IMAP plus a CalDAV/CardDAV sync addon. for mobile, z-push works mostly ok.