Before attempting the troubleshooting steps, TPG recommends that you:
1. Check our Service Status at https://www.tpg.com.au/support/problems_connect_internet.php
2. "Power cycle" your ADSL modem. This means turning your modem off and waiting for one minute before turning it back on again. This allows your modem to reestablish connection to our server.
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 your case, a TPG technician has been booked to further investigate the issue.