I answer with my business name and they always hang up. When I ring back Optus advises me the number has been disconnected.

Scam

Caller: Unknown

Very strong Indian accent. It was about nuisance calls but they needed my expiry date in my debit card. He said he was Telstra

Hung up when answering machine came on. Obviously a nuisance caller or scammer!

Said they were calling about my Telstra internet problems
we are not with Telstra -- I hung up after saying we were not with telstra

Called THREE times today. Nobody on the other end, then a voice saying 'Goodbye' and hanging up. Called Telstra - they blocked the number.

multiple nusiance calls - no one on other end

Tried calling back, message says phone number is not connected - check number and try again. Probably telesales.

Caller: supposedly "Telstra Internet Services"

Telling us our internet was going to be cut off in 24 hours.

We replied "OK" and caller hung up.

(Internet is still connected over 24 hrs later)

Caller: Apparently the do not call register

Caller states that they were from the do do not call register. Asked to verify my name and knew address. Asked me to verify the expiry date on my credit card. When I said I was not comfortable with giving over the phone she said she was disconnect my phone. Very thick accent

I couldn't understand the accent (I think Indian) but it was something about blocking nuisance calls. I hung up and then I was called back straight away again by the same number. I think this called was a 'nuisance caller'.