First Car Rental refused to refund me my fuel depo

I recently rented a car with first car rental whilst my car was being repaired. They took R1200 fuel deposit when I collected the rental car. when my car was repaired I then returned the car to first car rental. the driver who collected the car confirmed that everything was in order and he took the car and went. 30 minutes later I received a call from first car rental claiming that the Jerk and the tools were missing from the car. I objected to that as I had handed over the car with all the tools. The gentlemen I spoke to told me that even if I don't agree to sign a form that they were asking me to fill, they will continue to deduct the money for the tools. I logged a compmaint with the first car hire customer service and I was assisted by Khethiwe who then told me that I will be liable for half of the cost of the tools which is R1070 instead of the full R2140. I still do not agree with paying R1070 for the tools that I returned. infact the portion that I paid is the full fuel deposit. my worry is that this will be done to other customers and it is very unfair, it is a way of *********** customers of their hard earned monet. Please address