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We did an article that you may find helpful, this will guide you on how to track your NBN service installation. How to track your TPG service installation
Once the NBN service installation is complete you may proceed on setting up the equipment or the modem/router. You may check this guide.
In the event that you successfully set up the NBN service and still not working you may check if there is an ongoing outage affecting the service. See this link for reference How to Check for NBN Network Outage.
If there's no outage, you may perform basic troubleshooting step available in this article Troubleshooting no internet connection.
In this particular case, we've seen that the installation is still in progress, we chased this to our Provisioning Team, expect an update via Phone Call/SMS or Email within 24-48hrs. Should you need further assistance, feel free to search community for help or chat with us at https://www.tpg.com.au/support/contact/ and we'd be glad to assist you.