Hyundai Pinetown

I sold a vehicle to Hyundai..they did their checks in the workshop and they were satisfied and signed the paper work .then ensured me that monies will be paid into my account within a few days..they phoned me 2 days later to state that they want the deal canceled as they found faults ..they as the experts should have done their due diligence before signing ..now they are giving me the run around instead of payment .