Xbox won’t connect with wired Ethernet cable?

I have this same issue on my Series X. Was working fine for a couple days then it hard crashed (thanks CODBLOPS: Cold War!) and wen it came back the ethernet port is dead.

Submit a ticket through support (https://support.xbox.com/en-US/contact-us) which will lead you to your devices on your MS account (https://account.microsoft.com/devices/), you may need to add it. They will get you a shipping label to send the unit in for
repair.. not the solution we want, I know.

Are you using a wired connection? If your Xbox says the ethernet cable is not connected, have you tried disconnecting and reconnecting the ethernet cable?

.... finally get it online with a ethernet cable plugged in, so it now says no cable I can choose wireless?????? Now for the last 24 hours it keeps kicking me offline every 10 mins or so. Called live support and chose the hardware line NOT the live choice.
Only to be told by some idiot that I have chosen the wrong line and go back to the live support, so I hung up as this idiot had no clue what they were on about. Called the same number again, and got the same response.... to which came my reply " I would like
to speak to your supervisor". After a short wait I was speaking to a fellow who after some quick tests confirmed IT IS A HARDWARE FAULT, So I was calling the correct line. SIMPLE.... no cable plugged in and console thinks that it is = Hardware failure. I
do not hold much faith in their support if they cant establish that with their " Knowledge". Now do i return it to the vendor or M.S. for the best/quickest results?

If it's under 30 days - the vendor can give you a quick replacement, getting it to Microsoft it'll take ~7-14 days from the day they receive it to repair the console.

Hi, you will have to return it to store or if out of warranty Microsoft.