My friend had the same issue with their newly installed NBN
It normally take only 30 mins for the modem to get activated but in case it didn't you can manually configure the modem
If you have NBN FTTC you should have a TP Link VR1600
Step 1. Just connect your device to the modem via Ethernet or Wifi
Step 2. Go to http://192.168.1.1
Step 3. Enter the modem's admin login.
Step 4. Go to Advance Tab on top
Step 5. Go to Network on the left panel
Step 6. Under Network Click on EWAN
Step 7. Enter your TPG UN and PW and Click on Save at the buttom
See the Image Below
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We have located the account using your community details and we can see that your connection is up and running for more than 15 hours now.
This article about Wi-Fi No Connection can also help you:
Wi-Fi troubleshooting steps - No Internet/Connection
If you are still having issues connecting to the internet, feel free to message us. Thank you.