Ethernet adapter keep comming and going in settings

Hello all. i am trying to fix a friends network issue, his laptop is always connected to the wi fi and cannot connect to the ethernet adapter when he used to be able to, i have tried to update the drivers and when i do the adapter then vanished from the settings when i was there originally.
i have tried changing the ports on the router with no success, there is not realteck adapter in the


removed and reinstalled the network adapter, turned of the wi if he is running win 10 home i am starting to believe that adapter is partially damaged

all suggestions welcomed , Thanks in advance

The yellow triangle on the network adapter means it has a problem. Double-click on it to see what the problem is.

Ben

Thank you for your response it says the device failed to start error code 10 which i have looked up and i have tried all that the code says could be the issue and none of them has worked, i may have to go back to an earlier driver

hello i have managed to fix my friend network issues apparently his VPN was turned on, not by him, he was also on a public network.i now have him on a private network and an Ethernet connection and wifi now auto connects when the cable is removed