Connect to the Xbox Network

So about two months ago i bought an xbox series X and set it up using a Lan cable. A CAT5e to be exact.

I use Vodafone and have speeds of 500+mbs.

Turned everything on and it wouldnt connect to the xbox network. I restarted a couple times and finally it connected so i could sign in and download games and updates. After doing the update for xbox i was forced to restart and guess what. I got the same issue, Connect to the Xbox Network. Restarted and connected. Did a search as to why this was happening and tbh i dont think anyone knows the answer because cleaning the cables and ports did nothing. My xbox was brand new as were the cables. Anyway i got fed up with having to hope for it to work without constant restarts so i returned my xbox and they exchanged it. Now ive got a second xbox and guess what, it worked fine. Connected every time without issue, until the graphics card inside refused to read the games and i had to return that for an exchange. By now im really not happy. Third xbox means it must be lucky, right? Nope. Connect to xbox network back again. Called my internet provider who reset my network and router for me and it worked a couple times. Then i called Microsoft xbox who called me back saying its the UPnP. I turned it off and saved my settings. It worked once. Im now on my 4th xbox series X and still have the same issue. If i unplug the Lan from one of the 4 ports and plug it into a different port then it works, but why do i have to keep doing this just to connect to the xbox Network?? Network provider say its not a fault with my line and i agree because i still get internet connection. The wifi for other devices works fine but the LAN connected to my xbox refuses to remain connected to the xbox network more than it does.

Anyone else had this issue?

:)