Local File Problems

[TheVeilsHand]

Here is my problem, I have some local files that Spotify will let me play, but it will not let me add to playlists. This problem only occurs with a few files. I have done everything I could think of to fix this. The files are not corrupted, they aren't to big as I have bigger files that work just fine, I have tried restarting my computer, re downloading Spotify, and I have tried downloading them from multiple different converters nothing seems to work. I have tried to drag and drop into a playlist AND I have tried adding them manually by using the (...) button, but when I click the (...) button no menu appears, right clicking it doesn't seem to work either. I truly have no idea what is going on. Any and all help is welcome and much appreciated.

Thank you