Hekp with Spotify Script

Configuration
1

Why does the following script throw an error:

yam_spt_dis:
   sequence:
       - service: media_player.select_source
         data:
            entity_id: media_player.spotify
            source: 'TSR-7850 266CDA'
       - service: media_player.play_media
         data:
           entity_id: media_player.spotify
           media_content_id: 'spotify:user:xxxxxxxx:playlist:xxxxxxxxxxxxxxxxxxxxx'
           media_content_type: 'playlist'

Error:
HTTPError: 500 Server Error: Internal Server Error for url: https://api.spotify.com/v1/me/player/play

I do have a premium account and can play music fine otherwise.