lying on statements

I want to file a complaint against HOMECHOICE for sending me false statements. I receive statements that my instalements is 800 rand a month I paid them more the 2000 rand except the last two months witch I paid 1000 rand. Now their people calling me telling me I am in arrears with 5000 rand!!! How the **** is that possible? And she is telling me they charge me 60% interest if i don't pay that 5000 every month. So they send me a statement with a false amount or they are giving me a false information on the phone? They phone me every month asking if I want to buy something but now I am in arrears???? Their people are incompentent and they are very sneaky on their statement I will NEVER make use of them again and will NEVER refer family to them...... I want a full list of every single thing purchased and over exact total of months I asked for that ***0 times and only received my statement every month. I want it to close this account and never hear from them again.