why is one playlist works but other playlist is empty

SanDisk MP3 players SanDisk® Clip Sport
5

Since your question is new in this Forum, hopefully a few more expert users will provide better advice for you.

All I can say is my experience is with using mp3tag to create playlists that are saved inside subfolders in the Music folder of the Clip Sport (internal and external).  The playlist file structure using mp3tag does not look like yours.  

Here is a brief summary:

                   1st line

#EXTM3U

                  All other entries look like this:

#EXTINF : 3-digit number , Artist - Title [line feed] subfolder\filename

#EXTINF : 3-digit number , Artist - Title [line feed] subfolder\filename