SolMan 7.2 - Reassign Diagnostic Agent after OS Migration

Hello everybody,

After OS migration (Win2k8 > Win2k16), I'm not able to (re)assign the Diagnostics Agent in step 4 of Managed Systems Configuration. The following error message is showing:

A Diagnostics Agent is already assigned to Host <SERVERNAME>

The DAA was installed after SAP import via SWPM and in the Agent Administration it's connected and green.

A "Check all Host Agents" in the step brings up the following error:

Diagnostics Agents must be assigned before checking Host Agents

I've searched now for days an appropriate SAP note, but couldn't find anything.

An uninstallation and installation was also not helpful.

Any idea what would help to get step 4 green again?

Thank you

Best regards,

Tobias