A Director Penalty Notice is the ATO’s way of holding you personally liable for...

https://www.bookmarkingvictor.win/a-director-penalty-notice-dpn-isn-t-the-end-of-your-business-but-the-21-day

A Director Penalty Notice is the ATO’s way of holding you personally liable for company PAYG, GST, and SGC debts. The 21-day clock starts the moment the notice is issued