For customers experiencing any issues with their service, we recommend the best thing to do first is check if there's an outage.
Check our Service Status page for any known outages.
If you're on NBN, we have created this article that can guide you on How to Check for NBN Network Outage
If there are no known outages in your area, you can proceed with the troubleshooting steps indicated on this link : Troubleshooting No Internet Connection
If the ADSL light is stable, that only means that you are getting a line sync and no internet light indicates that your modem is not communicating with the TPG server.
In this case, you may need to manually configure the settings and we have created this article which may help : Setting up ADSL2+ and modem configuration
Should you need further assistance, feel free to search community for help or contact us and we'd be glad to assist you.