How do I play (or create a playlist) of music on my fire SD card within the music app. It does not see the musics files.

Aug 29, 2018
I moved many music files from my PC to the SD card on my kindle and they play individually by selecting them in the File Manager but they do not appear in the My Music category when the music player is activated. I can make a playlist in the music player but I have not found a means to install any songs in the playlist. Any ideas?