I've been listening to Spotify on my Echo for a long time until it stopped working today.
Spotify plays music fine on the Spotify app on my phone and on the Spotify app on my computer. In the "Connect to a device" menu, If I clicked on the Echo link on the windows 10 App it basically does nothing. If I click the 'Echo' link on the iPhone app is shows a message 'Connecting...' for about 20 seconds and nothing else happens.
Alexa is working fine ( 'Alexa tell me a joke'). If I ask Alexa to play music, 'Alexa play Bat out of **bleep** by Meatloaf', she says 'Bat out of **bleep** by Meatloaf from Spotify'. But nothing else happens. No music.