Poor service from Booking.com

On the October 3, 2019 I made a booking for an guest house in Kroonstad, SA through Booking.com. When I got to the guest house on 2019-12-05 Booking.com did not pay the guest house and the owner of the guest house cancelled my booking. I tried to contact them with no response what so ever, because I would like my money back. I think it was very unprofessional from them to do it.