Unhappy customer

I very angry because I have paid my account and I finished paying. I called one of their consultant and say I want to close my account she asked all my details I gave her, she said I still owe and I asked her how much cos I’ve been checking my statement every month. She failed to answer me and I have proof that I don’t owe I got it from them I received a message saying I should pay R550 . Trueworths is trying to **** me . I emailed them twice with proof and no one is responding my email