Angry costomer of capital debt specialist

It was last yr Sept when I joined their admin,same month I contacted them telling them that I want to cancel,they told me I have have to pay them R12000 cancellation fees,from Dec 2018 they started to deduct R3000 from my payslip.in Feb I contacted them reminding them that March was the last month they going to deduct the payment they agreed that they will stop,since March I've been calling them to tell them that they must stop deducting money from my payslip they haven't stop they still deducting the money and the will come with the excuse that they waiting for the court date,court date was 28 June 2019 when I call them they came with the excuse and tell me that they got another that which will be 30 of July,now I don't know what to do because now they owe me R12000 for the past month they been deducting my money and they told me that they owe me R2700 because they have more charges which I wasn't aware of.pls help I need them to stop taking my money because they won't be able to bring it back