***** fuel and use your vehicle without permission

Do not use them! I suspected fuel ****** and my car used without permission since I handed it in with half a tank and it came back empty. Next time I took a photo before handing it in and when I got it back it had been driven for 20km and 1/4 tank of fuel was missing. I immediately showed the driver and he also took photos as evidence. The owner is now refusing to contact me back and explain his poor service.