DDJ FLX4 not connecting to recordbox and virtual dj

Please, someone help me out. A year ago I was using Virtual DJ with my FLX4. I switched to Recordbox and since then I can't connect my controller to either Recordbox or Virtual DJ. Electric devices are not my specialty, I feel like a toddler.... Does anyone know how to solve this problem? A few more tries on my own and the controller will end in a bin....