So I made a playlist on my Mac consisting out of my own music and music I got from Apple Music. I, of course, made the Apple Music songs available offline. Now it won't let me sync that playlist to my iPhone because "iCloud Music Library playlists can only include music from your iCloud Music Library. This playlist can’t be uploaded because it includes other media kinds or songs that are not eligible." What's going on here? Am I doing something wrong? I assume I can make playlists from tracks I got from Apple Music, the whole point was that you could mix that with your existing library. Is this a bug?