Newish router from ISP, now changed for a different one (different ISP), it was using the Optic Fiber for getting internet to the flat.

Now when using it as an Access Point, it only works if I plug the Ethernet into one of the 4 LAN yellow ports. Can anyone confirm what is the “Internet” port for? and maybe why doesn’t get internet when plugged there?

Router is updated and tried both with and without the DHCP option enabled, same result, nothing.

Which brings me to the second question, once DHCP is disabled, I am not able to find the second router by its URL, gateway or IP address .

The main router will show the second router’s IP, but will be unreachable on the browser, and default getaway will bring to the main router.

This is the router used and its ports. Top purple Ethernet labeled \“Internet\” is the ~non-working?`