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If the connection suddenly stops working after a period of having no problems, here is a checklist that can help troubleshoot the problem:
1. Check the TPG Service Status at http://servicestatus.tpg.com.au/ or https://www.nbnco.com.au/support/network-status to see if there are any
notifications of maintenance or outages within your area. If so, please wait for the estimated time of repair given before trying again.
If your area is not listed on the Service Status, then continue troubleshooting with the steps
2. Check if the modem/router is getting power. Turn the equipment off and back on or try a different power outlet or power adapter with the same voltage.
3. Check that the ADSL cable from your telephone wall socket to your modem/router is properly connected at the back of the modem.
4. Check to see whether there is a dial tone on your telephone line by picking up a telephone handset connected to the phone port 1 of your modem/router.
5.. Try connecting your modem/router to a different telephone wall socket on your premise or from a different location (e.g. a friend’s house with TPG NBN) where you know the connection is working.
6. You may also refer to this link: https://www.tpg.com.au/support/nbn/troubleshooting_nbn_fttn
If the connection is still not working, kindly indicate which steps you’ve already completed to speed up the troubleshooting process.