eDreams complaint: Car Rental pricing discrepency

We rented a car through EDreams in October. We paid them $772 for a 4 wheel drive SUV. When we got to the car rental place (Fox) with the voucher we were instructed to bring, Fox said that they had only been paid $474 by Car Trawler who EDreams evidently uses to book the rentals. They refused to honor the voucher. We had to pay Fox an extra $210 to get the vehicle we had originally paid for. We complained to EDreams who just kept putting us off and then kept requesting the same information over and over without any resolution. We then disputed the charge on our credit card but they ignored the fact that we were not asking for a complete refund, just an adjustment to the pricing. So we have yet to recoup the $210 extra we had to pay for the vehicle. EDreams has ripped us off and then ignored our request for a fair partial refund.