Australia Reverse Phone Lookup

I've had about half a dozen missed calls from this number this past few days, and like a above, id call back and no answer.

Today they called me again when i finished work and I answered, turns out the Australian sounding woman is from Commonwealth bank inquiring about if i am interested in Life Insurance.
The strange thing is that the background noise was rather loud, like in a shopping centre, or something busy like that, and at one point she face dialed (pressing a number whilst on the phone, and it makes a beeping sound on your end).

The thing that i find odd that if it is commonwealth bank, why the hell is it coming from a Landline number? Arent their calls usually something blocked or something?
Weirdddd

I have had missed calls from this number 4 times this week. When I try to return the call there is no dial tone, just silence.

Number has called me twice in the last week.
First time I missed the call and tried to call back, not even a ringing tone was sent back. Just silence.
Second time I answered and was disconnected within seconds.

Sounds like a scammer.