horrible service

I have paid this driving school a lot of money to get my drivers license, including a guaranteed fee off R1500 which they said will be refunded if I did not pass have booked three times with them but only went for two test which both I failed, now that I'm asking for my guarantee money back they giving me hassles saying there will be deductions because its my fault which is untrue. I have had endless problems with this driving school an just want my money back.