This is a South Australian number - I didn't answer it as I don't know anyone in SA - let it go to voicemail, but they didn't leave a message.
Left it for 5 minutes, then I called the number back, after checking on here - "Your call could not be connected, please check the number and try again"

I didn't answer. No message. Google says it is a scam number. Now blocked.

Don't have any contact with South Australia, I didn't answer and Googled it where it came up as a scam number.

Same old, same old. I didn't answer adn wanted to hear the message but they didn't bother to leave it. Definitely scammers. I blocked the number.