Ethernet not working

[farmer_jack]

Hi
I have a Winstars Technology Ltd. docking station with displaylink software.

All worked fine but at some point, don't know when, the ethernet stopped working. Didn't noticed it because the wifi connected instead.

I have read a lot and tried everything I found, restart, reinstall, reconnect and much more, but whit no luck.

The other things work, its just the Ethernet that stopped.
It says that the cable isn't connected, but it is and the cable is fine.
What to do next?