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You might have a FTTB connection. Can you check this in your account details?
Do you have a wifi router from TPG or the one from your previous place?
FTTB may not need a NBN connection box.
I thought FTTB because you are an apartment block.
I don't think your old router is going to work.
TPG ought to have sent a new router for your type of connection there.
Were you ADSL at the previous place?
At www.tpg.com.au you can enter your street address to see what type of NBN you have. (Just underneath the picture on the home page.)