I am sure others have had this but I could not find it on forum so perhaps someone can direct me. I am talking about when Alexa definitely has the song and can play it, in fact she just has and has told you what it is so there is no question of this being to do with exact titles or pronunciation. Then asked for it again a few seconds later using her own exact formulation of what it is precisely, (which she then repeats EXACTLY RIGHT as when she correctly identified it ), she denies it is in library! This is nothing to do with mishearing, mispronunciation, regions or whether Amazon Music or Spotify, these are all constants. It is more like a sudden kind of blindness. She will still play the song if you stream the artist and go NEXT till it comes up.
On a more general note I only wish Amazon would stop with the trivia questions and get Alexa to be a thousand times more savvy when finding songs. She is right now completely hit and miss , even a 'the' not included or included can throw her.