We booked a shuttle from the hotel to the airport 5 days in advance, no confirmation mail, i sent them a mail, they never answered. The hotel staff helped us call them, the driver answered, and was rude. We decided to cancel it, the hotel staff tried to call back for 2 days noone answered. So we did what made most sense, block the credit card just to make sure they wouldnt be able to charge for something we didnt get. Booked a shuttle service with the hotel for the same price.
In short, NEVER use parisshuttleservice