Presently, my fixed phone line is out of order, so I use my smartphone to keep accessing internet with my PC through a USB connection to the smartphone (my PC is fixed and has neither bluetooth nor wi-fi device).
That fixed PC works under Windows 10 and has 2 LAN cards: one goes to the internet box, and the other one to an ethernet switch to integrate the local home network. When I connect my smartphone to the PC, I can see a 3rd LAN card in the list of LAN devices.
But here is the problem: the Internet access doesn't work though the smartphone is shared, until I de-activate both my LAN cards (I'm in this case right now as I'm writing these lines).
So here's my question: How can I keep access to Internet through my smartphone without having to de-activate my LAN cards?
Thank you by advance for your help.