Hello Cloveracy,
Thank you for using Apple Support Communities. Sounds like you're missing some songs from your Music library. If so, we'd like to share some information and see if we can help out. Sometimes certain situations might cause you to lose data such as music. For example, if you're an Apple Music subscriber and you turn off Sync Library, this can cause music to be removed. Also, if you sign out of your device. linked music, movies and other purchases will be removed.
However, if you didn't do any of the above, you might still be able to recover your music. If these missing songs were purchases, you can redownload them from your purchase history: Redownload music - Apple Support
Redownload music from the iTunes Store in the Apple Music app on your Mac
Before you can redownload music that you purchased from the iTunes Store, you need to authorize your Mac using your Apple ID.
1. Open the Apple Music app.
2. From the menu bar at the top of your screen, choose Account > Purchased. If you use Family Sharing, you'll see Family Purchases instead of Purchased.
3. Find the music that you want to redownload. If you use Family Sharing, choose a family member next to Purchased to see their purchases.
4. Click the download button
next to a song or album.
If there were not purchases, but just additions from the Apple Music catalog, you might have to manually add them back: Add and download music from Apple Music - Apple Support
Additional steps you can try is to make sure that your iPhone is fully updated. This can help resolve unexpected software issues: Update your iPhone or iPad - Apple Support
If your music continues to disappear, we strongly encourage that you reach out to Apple Support for help. They might have to continue to investigate this issue with you. Use this link to reach them: Get Support
Thank you for using Apple Support Communities. Take care.