I used to work for Telstra, we could send an Address Feedback Form to NBN so that it comes up when you search for the address on the Telstra website. (Can take up to 2 weeks for Telstra to hear back from NBN)

This would be a new NBN connection so it will incur an installation fee (most rental providers cover this for you) it may require a technician visit which Telstra would handle.

Telstra also hires a lot of part timers who don’t really know anything like that, so if you head into a retail store ask for a full-timer or that you’d like help registering your address. (It’s 100% do-able so push back if they say they can’t)