Welcome to the Community!
We were able to locate your account using your community details and it appears that the configuration of your new modem/router is incorrect. You need to use your TPG username or customer ID number to get the internet working.
You may use this article as a guide: How to set up your TP-Link VR1600v modem?
To confirm that you have the correct TPG username and password, you may try to login here: https://www.tpg.com.au/myaccount.