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I tried to google D-Link DVA-2800, it shows that its a ADSL2+ and VDSL2 ready which means you simply need to set VLAN ID 2 together with your TPG username and password and it should work.
Note: NBN VoIP service will only work using our supplied modem/router.
You may also visit this existing thread below for reference on how to set up 3rd party modem/router for TPG NBN FTTC.
Third Party Router for NBN FTTC.
Let us know should you require further assistance.