Welcome to the Community!
I'm sorry about the disruption of your service. Based on the tests and the assessment of our Helpdesk Team, there's a fault on the line that needs assistance from NBNCo.
From what I can tell, this was already raised to NBNCo and an appointment has been booked for you. Our records show that you agreed to the said schedule as well.
Your attendance is required for this particular appointment. You may also delegate someone of legal age should you be unavailable. Feedback pertaining to the outcome of the tech visit will be provided to you directly by our Engineering Team.
If you have questions or need clarification, feel free to leave us a message.