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Thanks for raising this with us! I was able to review your case and you are correct, your connection was intermittent prior to the NBN box going offline completely. It appears that NBNCo has raised series of outage reports from July 13 - 15. Since they have already declared that the outage has been resolved, this needs to be raised to NBNCo for repair. I have escalated your case to our Engineering Team for assistance. You will be provided updates via SMS or phone call within 24 hours. Should you have questions or other concerns, feel free to leave a comment.
In addition, can you confirm if you have performed a reboot on the NBN box? NBNCo has left a recommendation on the outage ticket they've closed stating that if the service isn't working, a reboot may do the trick.
Nonetheless, the case has already been raised to our Engineering Team.
I can see that you were contacted by our Engineering Team already and that you were informed that this has been reported to NBNCo. From what I can tell an NBN tech appointment has been booked and that you have already confirmed your attendance.