Caller: Claims to be from NBN

Automatic message telling me that my NBN has been disconnected but to hold on the line to discuss with a staff member. When the staff member answered, they had a thick accent which was hard to understand but she stated that my internet had encountered a problem and had to be turned off but she would help me rectify it. As I was using the internet at the time, I told her I could see I was still connected at which point she terminated the phone call. Out of interest, I tried phoning the number they had rung me on but only an automated message stating that the "call cannot be completed as dialled..." answered.