Robbing from the poor

I'm an unemployed mother of 2. SARS decided to do an audit on me and say I owe R77000 for 2014 and 2015 tax years. We have phoned and been to see them at their offices numerous amounts of times and e-filing won't let us register a dispute. I own nothing and earn nothing and I live with my father who is threatening suicide over this tax bill that we cannot pay. Please can someone help us. This can't go on, my father is going for an operation in 2 days and he's not sleeping at night over this.