NSFAS *****

I requested a settlement letter with nsfas in 2 January 2018, and the 4 January 2018, I make a full payment and requested a settlement letter or closing balances. But since then I haven't got any response from them and fast forward that to November 2018, I received an email from them saying that I owe them a lump sum of amount of which I don't understand how was it calculated. I am not going to pay them any cent , we might as well take each other to court because this is ***** what they are doing