Pathetic after service and try to ***** customers deposits

Can someone help or redirect me to a competant persom at WeBuyCars for help.Ive called customer cars numerous times and lodge several complaints.Even tried to contact Ceo Faan van der Walt. I bought a vehicle from Port Elizabeth branch on a auction.After fully paying for the vehicle right after the auction,the sales person contacted me and says the vehicle was taken for a test drive a week prior to the auction.The vehicle started smoking,had water leaks and his exact words “i do not feel comfortable selling you this vehicle”.I then told that i do not want the vehicle anymore as those faults was not indicated to me before the auction started and also not on Dekra report.Now after a week,im still struggling to get my refund from them and they want to keep/***** my R5000 deposit for the auction.How can i be reliable for something that is not the clients fault by taking my deposit??