Local Files Not Fully Appearing

[Yunn]

Hi all, I've recently encountered a problem with local files. 

Previously, I faced a problem with it and I used the solution that was linked on Reddit with installing an older version of Spotify. However, all of a sudden, my Spotify is not synchronising all my local files again.

I have a separate folder under my Music Library named Spotify with about 6 tracks in it that I'd like to import onto my iPhone. They used to show up on my Desktop app and was also synched over to my iPhone, but they're no longer showing up even though I didn't change any settings whatsoever. There's only one song in a .m4a format that shows up, while the other files are a mix of both mp3 (3 files) and m4a (2 files). I've restarted my laptop and my desktop app multiple times yet they're still not showing up. If anyone can help, that'd be great!