I feel I am using it in Wireless router mode but could be mistaken. I am NOT using the DSL port on the old router/modem and connecting via the WAN port to the NBN modem. Do you recommend a...

@Marvin_S Yes I have the Archer VR 1600v ISP is TPG and have NBN HFC.

Trying to setup Archer Ax80 to replace my old Archer 1600. I am met with a No Internet Connection message with orange light on Internet of AX80. I don't believe the hardware connection is the issue...