Defying the consumer protection act

I bought a car from ps car sales. Deposited the funds to his account. I pulled out of the deal within 5 days. He refused to refund all the money I paid him. He kept R4000.00 of the R44000.00 I paid him. And that's against the law. He knew I had no car and the law issues would take time. And he took advantage of my situation. So I lost R4000.00 .I had to sign a letter stating that he would refund me R40000.00 of the R44000.00.I did sign it to avoid losing all my money. And he did refund my R40000.00.