Welcome to the community!
We did an article that you may find helpful, this will guide you on how to setup the newly installed ADSL service.
See link below. Setting up ADSL2+ and modem configuration
In the event that you successfully setup the equipment and still not working, we recommend that you do the following below.
If you are still unable to connect to the Internet, you can proceed with the troubleshooting steps indicated on this link: https://www.tpg.com.au/support/problems_connect_internet.php
In this case, we've seen that the installation has been completed and there is a line fault causing the service not to work. We escalated this issue to our Engineering Team for further investigation, updates will be provided when it becomes available via SMS/Phone Call or Email.