from the article:
The government has intensified its efforts to retrieve debts from low-income Australians since mid-2015, when it began using a new automated data-matching system to detect overpayments. Since the system was introduced the number of compliance letters being sent by Centrelink has jumped from 20,000 a year to 20,000 a week.
Recipients are given 21 days to dispute the debt online, forcing them to track down payslips and employment history from up to six years ago to prove they did not wrongly claim benefits.
“If you do not respond, it will be assumed no reasonable excuse applies and the 10% recovery fee may be added to the debt amount,” the letter warns. But problems with Centrelink’s online service have left some users unable to lodge a dispute.