You may need to contact Telstra to get the address added either by calling 132200 or by sending a message using the My Telstra app on your mobile (blue icon, bottom right of Get Help screen), and if Codi tries to redirect you, type "Speak to a consultant" and you should get transferred to the queue to chat to a human.
Before calling (or messaging) go to nbnco.com.au and type in your suburb/town and zoom in to your property and drop the pin on it to see what addresses come up. If it's not listed there, then you will need to ask Telstra to get NBN Co to update their database (at the very least, it will give you some extra information as to what is going on in the background).
Never be afraid to back yourself when trying new things, just always make sure you have 3 escape routes if things go wrong.
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