I actually owe them $6

My case is a bit different. I started working in the second half of 2015. Before this I had been a stay at home mum for nearly 20 years, raising 5 kids. When it came time to put in my tax return for 2015/2016, I had to link the ATO to MyGov.I was surprised to see two tax returns sitting there, unlodged. One was for $5 the other was for $25. I queried what they were, as I always told Centrelink I don't need to lodge a return as I don't work in paid employment. I was told I had to submit them before I could submit my current tax return. So I did. I thought nothing of it. Shortly after I received two bills from Centrelink - one for just over $4000 and the other for nearly $3700. It turns out that if you are late lodging a tax return, you are not entitled to receive any FTB supplements. I had no idea these returns even existed before linking my MyGov to the ATO. The amount it relates to is $30 over two years. It turns out it was bank interest. As this income reduces what I am entitled to by 20 cents in the dollar, I actually was overpaid $6. Instead I owe $7700. I am appealing but it's been months and in the meantime I have had to start paying it back to avoid it going to a debt collector. The worry is constantly on my mind. I lie awake thinking about it, then when I finally go to sleep I'm up at 4.30, worrying about it again. It's so unfair. Athe least with the other debt letters they are only asking people to pay what they think was overpaid - in my case they want me to pay well over 1000 x what I actually owe.