This is only what happened with my German version of Windows 11.
In a second test, I did the same with a WAV file and you are right, "djay pro" does not seem to read the ARTIST and COMPOSER fields for WAV files:
Mp3tag fields in WAV file:
As we don't know what field names "djay pro" expects for WAV files, there is not much we can do in Mp3tag for this WAV file.
Perhaps you should ask on the Algoriddim forum how other "djay pro" users solved this issue?