My Hori LAN ethernet adapter for the Nintendo Switch just failed one day, it wouldn't even light up when I plugged it in. I tried all the USB ports, I tried various combinations of undocking the console and unplugging the AC. I tested the adapter on my laptop and it worked fine. I looked for a solution online and there was no help, someone made a thread on Nintendo's support forums, there were many cries of others having a similar problem but ultimately no solution was provided.

I don't know if search engines will pick this up but here's what I did: I had to TURN OFF the Nintendo Switch (hold the power button for 3 seconds, select "Power Options" and then select "Turn Off"). When you simply press the power button it puts the Switch to sleep which doesn't flush the RAM and holds all the faulty power settings that may not allow USB devices to work. It's a good idea to TURN OFF the switch every now and then, it sucks that Nintendo made it difficult to access such a simple and necessary feature.