Europcar - petrol top up ripoff

<p>I rented a car from Europcar at CT airport a few months ago (Feb/Mar I think). I topped up their petrol as I alays do when returning the car. In this case the tank was topped up at the petrol station adjacent to the airport. When receiveing the final bill from them the added an amount in to top up the car again. I had exactly this same experience a few weeks earlier at King Shaka International airport. I send the Europcar at CT Airport the copy of the petrol slip with the date and time on it but they have been ignoring me for months now despite my regular requestes for feedback. </p>