First off, I'm sorry if this problem has already been brought up (but I don't think so).
These last couple of days, I've been having trouble with adding songs to my favorites. Usually, when I want to do that, I either click on the cross under the cover of the currently playing track, or I go to the artist page and add the songs from there. But, apparently, only the first option seems to work (kinda), meaning only then it appears in my favorites. Furthermore, I added Spitfire (by The Prodigy) that way yesterday evening at home, but when I opened Spotify at work this morning, Spitfire was gone from my favorites (along with a couple of other tracks I painfully added yesterday evening).
This is a very recent issue, I think. Am I overlooking something or is there really a problem?