My family and I stayed at Pierre & Vacances Les Jardins de la Côte d'Opale for a New Year break. On checking my credit card statement upon my return, I noticed that we had been charged twice for our stay. I raised this with the agent we booked with (booking.com) on 4th January 2010. They assured me that they would deal with the error and advised they were in regular dialogue with the hotel to resolve the matter. Despite numerous chasing e-mails and providing them with a copy of my credit card statement to prove the double charge, I have still not been refunded (5th Feb). So from a customer service perspective (making the double charge error in the first place, time taking over a month and counting to resolve and putting the onus on the customer to prove the error), very, very poor.
