Very rude and pathetic service from The DP

Hellopeter , I have dealt with Toyota midrand today to purchase a Toyota Fortuner cash . I went in at 2pm for a test drive and advised the salesman that I will contact him later that afternoon of which he made me fill out a long form etc etc. I called him today afternoon only to note that another salesman is selling it to someone else with. I then asked the DP if an offer to purchase or deposit had been paid and he said the salesman didn't get an OTP signed from the buyer . I then suggested I will sign the OTP of make payment and the DP was rude and arrogant to me and said the car belongs to the other person because his salesman is the best salesman etc etc etc and was negligent by not singing the OTP .Please advise me on the next steps because im surely not accepting this and will do everything in my power to challenge my rights of being the first buyer. BOTTOM LINE IF YOU NOT WHITE AND SPEAK AFRIKAANS DONT TRY TO GET ASSISTANCE FROM THE DP OF TOYOTA MIDRAND ....