Can't get refund for data overcharged

Autopage still owes me R 4455.22! <br> Since I changed to my current package in 2014, my account has been messed up. I am supposed to get 1 gig CellC data FREE per month. But they kept billing me for this free gig, and at 99c/Mb out-of bundle rate, they've been overcharging me with R1013.76 per month. <br> After struggling forever to get my refund, they refunded me thrice, and it does not come close to covering the money they owe. I'm still trying to get the rest of my money back. <br> Their response about the data overcharge is that their computer system cannot apply the 1 free gig to my account. This is not my fault they couldn't update their system - how do I get my money back now that the company is closing? This so so frustrating!!!<br>