I refuse to wait 15 days for a refund

Owner of 1128 Blyde Luxury apartment cancelled booking just after I made payment. He alleges double booking to the property. I need to make another booking but I have to wait up to 15 days for a refund. I refuse to wait that long, I need to book another place with the funds, its the owner that cancelled not me and its the app that double booked not me. I need immediate release of my funds.