Exchange / Outlook automatically accept dayly the same meetings for one user

Since some days Outlook is dayly auto-accepting meeting invitations from a specific user.

What happens

• Mail: "Microsoft Outlook has agreed to this meeting in the order of [employee2]"
• The mails come every day at the same time
• They usually accept every day the same meetings
• All meetings seem to be periodically meetings (like yearly birthday - reminder)
• No automatic accept or decline is set in outlook
• no rules are defined
• The meetings are on both accounts present
• Only one user is affected

Using
Exchange Server 2016, Windows Server 2016, Outlook 2016 on Terminal Server 2016

History
The complete IT was new installed in june (including active directory). All Mails, Meetings, ... has been exported and imported using PST files.

What i did so far
Similar behavior found here (in this case Exchange is periodically recreating missing meetings) https://andys-tech.blog/2017/02/exchange-users-receive-meeting-invitations-from-declined-instances/

Here a "Calendar Repair Assistant" is the cause. There seems to be a way to stop the "Calendar Repair Assistant".

From the log
I looked in the logs of the "Calendar Repair Assistant" There is the name of the old server stored. But only one user is affected, so it shouldn't be a general problem.

<89B4B51C6F61BD4CA7BDFCE66559077EBB4379@SERVER.OldServerName.local>

Questions

• Should the "Calendar Repair Assistant" be stopped?
• Does this behavior indicate a deeper error or misconfiguration?