HELP PLEASE!!

Do not rent from Thrifty. System error online when booking. made two deductions of in the R2500 round for my car rental EACH. went to airport to book it, paid for rental. Did not receive our twice deducted booking refund. ABDUL MALIQUE stated he would do it immediately when taking the car back. Now one month later... Rented again, still no refund of about R6k. Then took a holding deposit of R7000. Deducted everything, never received it. They have said it should be refunded. So in total thrifty owes me R13k. I call and call and call, WhatsApp ,email I get fobbed off each time!!! Called extensions, keep getting directed. PLEASE CAN SOMEONE ASSIST!! HELP HELP HELP!!!!