MP3 file for example is added to your device locally using iTunes. In my iPad’s case, I only have locally stored music files which, up until the last update(27 Nov 20 - 3.5.12), where accessible by DJay pro AI.
What I have done to try and remedy;
delete all music files stored locally then reinstalled them
uninstalled and reinstalled DJay Pro to latest version
revoked and approved access to Music
uninstalled and reinstalled the Music application
DJay Pro (upon fresh install) asks for access to Music - I accept
When I select Music icon it shows 4 options; Playlist, Songs, Library, Queue
If I select any of the options … songs for example, it just shows the spinning wheel endlessly - no error message etc
It renders most of the cool things DJay Pro is supposed to offer in accessing and processing history, files, playlists etc useless unless I use SoundCloud, Tidal etc.
As I say, the DJay app working just fine until the last update and I haven’t altered anything specifically that I know of.