Caller: Said it was ANZ

Missed call, I called back (ANZ) and a man with a fake American accent immediately started asking account details.
Sorry mate, not giving you any info.
If it is the ANZ they should already know who they called.

Caller: (03) 8565 0019

Today they rang to the office and asking for a colleague but days before I received silent calls from this number.

I received about 5 - 10 calls per day from this number. I don't answer anymore as it was a silent call every time. It has become extremely annoying

You answer and no one is there this has happened a few times.

Nothing on the phone so i hung up

Caller: (03) 8565 0019

Missed call > called back and claimed to be "ANZ Bank" automated messaging requesting input of CRN details, etc.
HOWEVER my mobile screen display had "(03) 8565 0019 Clayton" not ANZ.
Have received missed calls on two consecutive days.
I had no reason for ANZ to contact me unexpectedly. https://www.anz.com.au/security/fraud-detection/latest-security-alerts/

Missed call i called back and it said"ANZ Bank"