u/WillingObscurity

I’m in UK with Vodafone pro 2 broadband. WiFi 6e router.
I also have lan ports (3) beside the ONT. (in cupboard)
These enable the lan ports in the living room and bedrooms.
I can plug an Ethernet cable from ONT to the 1st lan switch (in cupboard) and router to that matching port in living room. All good.
If I then plug the same cable from the ONT to the network switch & then another cable to the lan ports (in cupboard) and then the router to the activated living room ports then the router will never connect.

This should work right? Or am I missing something really obvious.