This is a scam, they use many different numbers, I believe calls come from India. I have tried to report them to the "do not call register" but no help as they can not help with illegal activity. I had to change my phone number.

I rang back the number (02) 8378 7947, spoke with someone who hung up right away

Lady laughed and then hung up. Another nuisance call from numbers beginning with 02 8378....