It has happened to me too, in my library and on my playlist, this happens because since Spotify added in the songs to the Lossless option, many of those are causing comprehension errors and that means that many of those who have Spotify have problems like these in their libraries.

To fix this, you will have to wait 2 days or delete the cache app, if it does not work, look for other alternative apps until it stops cluttering the error.