Adding Custom sounds to Custom NPC?

[Little_Luna]

Alright, I've tried almost everything to add custom music to the Custom NPC's mod, I've followed the Tutorial's which were for Resource packs, but it is the same code structure in the songs.json right? I think I am doing something wrong, or missing something. The log says this whenever I try to play the music [05:16:03] [Client thread/WARN]: Unable to play empty soundEvent: customnpcs:Daylights.End  It does show up in the Sounds list, but it doesn't play, I've even tried with a sound pack I downloaded from the mod maker's site. Does it have to be zipped and put in like a resource pack? Because the Zip structure of the sound pack was similar to a resource pack. :/

If I am doing something completely wrong please tell me, I really want to fix this problem, I know, I'm not the only one with this issue.