NR7101 - setup instructions to WAN port on UniFi Dream Machine

hi all, I have just got a NR7101. I have inserted the SIM card and can see it’s connected, the light on the NR7101 is Green. I can connect to the WiFi and configure the device.

I have it plugged into the PoE injector that came with the device, so all good so far.

I have plugged a cat6 cable from the injector to the WAN port on my Dream Machine - no connection, no IP address and no LAN connection in the 7101.

I have also tried plugging the Ethernet cable into a laptop and do not get an IP to internet connection.

any ideas please