Issue Plesk Premium Mail Calendar Error after 18.0.46 Update 1

[drdna]

Server operating system version

Ubuntu 18.04.6 LTS

Plesk version and microupdate number

Plesk Obsidian Version 18.0.46

All Calendars from Plesk Premium "exchange" mailboxes are Corrupted after 18.0.46 Update 1 Update, and one mailbox wont sync with active Sync anymore....
Reinstalled Plesk Premium Mail...
Does anyone else have these Problems or can help me?