Welcome to the community!
For newly installed NBN service, we did an article that you may find helpful.
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 I can see that your NBN installation is still ongoing updates will be provided by our NBN provisioning team via SMS or Phone call. While waiting for the installation completion, we recommend to use the ADSL2+ service.
Unfortunately the ADSL2+ service is not at the moment due to line fault. We have identified that the issue is with the network controlled by Telstra. This unfortunately means only Telstra. We chased this with our team, updates will be provided via email when it becomes available.
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.