Booking.com Double Booking Due to System Error and Unresponsive Customer Service

On June 16, due to a system and interface error, we made two reservations for the same hotel for June 17 through Booking.com. It was non-cancellable, but the hotel approved and accepted the cancellation. A month has passed, and we are still waiting for our refund from Booking.com without any response. I am very disappointed with such neglect from this organization. We have sent numerous help emails and are still waiting for a response, being stalled under the guise of procedure. The hotel fulfilled all their requests while we were at the lobby, but they are still stalling with procedures. I want my refund processed as soon as possible.