can't install Fail2Ban or "plesk repair installation". Plesk thinks my i am still on version 12.5.30

Product version: Plesk Obsidian 18.0.23.4
OS version: CentOS 7.7.1908 x86_64
Build date: 2018/12/14 14:00
Revision: 6a5bd1208852d9cc63e7c2099f18709b1f2e7852

I can't install Fail2Ban or anything else via Plesk.

plesk repair install exits with result:
Unable to upgrade. You have 12.5.30 version installed,
but the upgrader is incompatible with this version.
Please consider using migration instead of an upgrade.

Click to expand...

Any Idea how to solve this?

/bnpot
The content...

can't install Fail2Ban or "plesk repair installation". Plesk thinks my i am still on version 12.5.30