I had a call from this number, which I did not recognise. I searched for the number using this website (reverseaustralia.com) and it reported that no results were found. When I called it back, the next day I received the message that this number (02) 6648 1505 was "not in service". I suspect that in the meantime this number has perhaps been investigated by someone else, found to be either spam or something more dangerous, and has been either blocked or deregistered.