I also had trouble canceling a reservation at the end of last week. A friend and I had each made reservations and decided who ever landed first would get the car -- that ended up being my friend. My carfirmation reported that Hertz assigned a Jaguar XS on my midsize reservation so it was terribly painful to cancel -- but you gotta do what you gotta do. I was however unable to cancel. Hertz did not charge my card.