booking.com ******* service

I made a booking through booking.com, the establishment called to say they are fully booked and have closed their bookings midday, however booking.com went ahead with a booking and taking my money. Now i was stranded with no place to sleep and no alternative because they have my money. I called their customer line and got a robot, that told me its transferring me to customer service, i held for 15 minutes and they hung up on me. They still had a nerve to tell me to rate the establishment but could not reply one single email. I want my full refund and will never use their ******* service again, they are ****mers.