Thousands of people forced to pay back part of their welfare payments due to suspected computer glitch

from the article:

Some doing it tough have been incorrectly referred to debt collectors due to a suspected glitch in Centrelink’s computer system, which has sparked a string of complaints from people being accused of owing Centrelink up to $10,000.

The computer system was put in place six months ago, and it went from sending 20,000 letters a year asking for people to pay back money, to 20,000 letters a week.