OH3 MI and Homegear installation

No you haven’t.
First, you are missing the point that homegear is not openHAB and as such this is the wrong place to ask about your issue.
And you haven’t even read the openHABian debug guide which should be the starting point as obviously your Homegear installation is broken in one way or another.
You have not provided any logs or version information whatsoever which is the minimum if you want others to help you which is what you ask them to here.

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