Unsupported file error

I have been struggling with this for the past month, MOST of the new tracks that I buy/import to rekordbox, be it wav or mp3, tracks downloaded from bandcamp, don't open on CDJ. I tried deleting the tracks and re importing them, nothing happens. it's as if something changed in the settings of rekordbox, because I never had this before and for the past month it's happening everytime i try to play a new track. it's really messing up my sets and i need to figure it out asapp