I called back number (02) 9112 3834 reached IVR for a company called Contact Center Australia.

This number called and said that they were from Telstra and claimed some illegal activity was going on with my internet. I hung up.

They hung up when I answered

I called back after being seriously interrupted by a call from this number - with no message left when I failed to get to the phone in time. The recording said it was Call Centres Australia phoning on behalf of a client - and that if I wanted to speak to someone I had to call another number. No chance: it's easier and cheaper to block the number.

phoned and hung up - line busy when I phoned back

unknown person called my home number every day this week sometimes 3 times a day. whenever i answer it they hang up. have no idea who it is, what company or anything else as call backs to the number results in a hang up their end.

they hung up when I answered