First Car Rental - Awful/unreliable booking system

I tried to book a car with First Car Rental at the end of last year. Did the online procedure and was told email confirmation was going to be sent to me to complete the order. The email never arrived so I assumed the procedure had cancelled, and so I booked with another company. 2 weeks later as my job is starting I get a confirmation email from them for the booking. This was the first communication I had received. I called to notify them that the booking was never completed and hence never booked, to which I got a follow up email confirming the booking was cancelled. I thought that would be the end, but I've now noticed they deducted a deposit of over R2000 from my bank account which has never been refunded. In summary their booking system is highly unreliable, and Im not even sure if its legal to be able to deduct funds without completion of a booking. I highly recommend you do not use this company, they will waste your time, leave you and your plans in limbo, and ultimately they will still take your money.