Refund not paid over 30days

I am really sad about our experience with booking.com.Last year December our accommodation was canceled due to the place was no longer in business. To-date we still have not received our refund of R12000.00. What more are we supposed to do from calling with our airtime, sending emails. Really such a huge disappointment. I hope this review will have people looking into who to trust.All we want is our money back.