Scammer, heard a click when I said hello as if someone was trying to get a voice recording.

Got a call on this number, rang back only to get a "disconnected service" message.

Scam.

My phone's software automatically flagged this number as a Spam call.

A male pretended to be from Mastercard calling about a suspicious transaction. He became aggressive when I said I'd call Mastercard directly.

Just hung up when picked up!

amazing ... a phone call came through with 3 different caller ID no. simultaneously. The above number plus 0431 626 250 and (02) 9071 0272 (this no. has been reported as an attempt from scammer).
I presume it is attempted scam call. proceeded to block all 3 numbers.