So my UDM died last week and bought a UDM Pro as no stock of the basic one. 

Problem is I can't for the life of me set the bugger up.  The UDM was easy as (change to advanced setting and add VLAN tag of 10)... not the bloody pro.

I'm using the app, it discovers ok, I change the DHCP to VLAN 10 and hit save (pic below), and still nothing. Have restarted both, the UDMP, cable modem and app. (Note, I'm not a pro at this stuff!!)

What am I doing wrong?! Are there other settings I'm missing on this sucker? 😢 Really hoping it's something obvious to someone in the know and simple too.

(might be worth noting that when I go into the DHCP setting again after it fails to connect, the VLAN isn't set and have to redo it).