Europcar is *****ing money from our deposits and doing nothing about it!!!!!!!

Europcar and their service is pathetic! My insurance hired me a car through Sandton Gautrain Station. I drove the car for 70kms and upon return of the vehicle and deposit, they had charged me a refueling fee of R390 even though I filled up the car with whatever I have used. Up until now, I have not received an invoice, even though I requested it numerous times! Logically speaking, how can 70kms of driving use up R390 worth of petrol???????? When i asked the guy that, he said he will look into it and get back to me. Up until now, nothing!!!! How can these guys just keep taking money out of deposits and not care??????? We work hard to earn this money! We fuel up your cars and return it and you still ***** our money!!!! I will never recommend Europcar to any person ever!!!!!