I want to use my Echo Dot 2nd gen to play music from Spotify to a Sonos player. I followed instructions and had it working no problem. Now, however, when I ask Alexa to play something from Spotify I am told I must link my Spotify account in the Alexa app. When I go to the app, the Spotify account is shown as linked. I unlinked it and relinked it. Alexa still tells me I must link my Spotify account in the app. Any advice on how to solve this problem? Thanks.