Formatted USB Flash Drive File Reading Issue

My USB was full, so I reformatted to FAT32 original settings and put it back in rekordbox. It recognised my USB, I transferred my playlist onto it and the playlist is on it as confirmed by the sidebar on Rekordbox. When I plugged it into my XDJ RX, it flashes like its reading it, and then it is empty and doesn't show anything but and empty table on its screen. I can't see what I've done wrong! Any help would be appreciated. 

Miles