I found when I restart the NBN box, the UNI-D 1 light will turn to green for maybe 45 seconds and then becomes dark and the router setting page said the status is WAN unplugged. But during that 45sec the internet status page appears the router try to link the NBN box, and after 45sec there is a cross on the status. And during the 45 secs, the part of internet light on my router showed a red light. After that, the UNID1 port light was off and so does the routers' internet light.
I have read somewhere that this means you have the wrong serial number for the NBN NTD box.
I enquired about this on Friday and still no word, I need this fixed asap as I work from home.