Welcome to the Community!
If you are using the Netcomm NF7, then it means that the NBN technology you have is FTTP (Fibre to the Premises). For this type of technology, you don't need to set the VLAN ID to 2.
Make sure that your device is running on a 'Router only' mode, then configure the PPPoE with your TPG username and password. Make sure that you have the correct UN and PW by logging in here.
You may use this article as a guide: How to set up TP-LINK C1200 modem for Windows 10