Monaco Guesthouse and Booking.com took my money and non of them is responding.

Booking.com charged me for booking to a guest house which they are no longer in trading with (Monaco Guesthouse at Bronkhospruit). The guesthouse manager told me when I get there that they are fully booked and no longer with booking.com. I have sent emails regarding my refund, but both Booking.com and Monaco Guesthouse are not responding.