I called the number and someone with an Indian accent saying he is the ATO.

Caller: Scam - recorded message

This is a threatening voice message about tax "avoidation" (how wonderful the scammers make up a word rather than use a real word "avoidance"). It threatens a warrant for arrest and says the issue is "very time sensitive."

Please don't press the buttons and end up speaking to a real person. Hang up and block the number.