This number called my phone 20+ times. I didn't answer. My phone flagged as potential fraud. I called back with private Caller ID and a recording states: Optus advises that the number you have called has been disconnected.

Scam call.

Received many missed calls from this today too but I don't recognise the number

many calls over last 2 days. never leaves a message. If call back then says "The number you have called is not connected".

Someone with an accent called and knew my first name. Just hello? hello? Mr. xxxxxx. Hello?

Seriously, leave a message or piss off.

Just left a message saying “hello?”. Annoying.