Can't load any tracks onto DDJ RX controller

The controller is coming up as recognised on my laptop audio and device settings and if I play tracks by using my mouse cursor on Rekordbox, it plays from my connected speaker, and shows on the master level indicator on the controller. However I cannot load the track into any of the decks or use the rotary selector to choose a track. I'm in performance mode. I can't use any of the buttons other than master level on my controller at the moment. I have updated the firmware and Rekordbox. Please help as I have been trying desperately to make it work and I can't seem to figure it out.