I have no idea how to contact any support team. There's no number and the chat is not working. Literally, where are you guys? My modem suddenly has no power. All lights are gone. Please come over and fix!
Is it the nbn connection box or the wifi router?
Depending on the model, there may be a power switch, maybe at the back.
Try a different power point. Otherwise, a faulty unit.
I can't help you further. You should make a normal post here and wait for a moderator. Do a post now and if there's no reply during tomorrow morning, do a repeat.