My google home mini (before Nest) is having trouble maintaining consistent connection to my Spotify account when streaming music. I would select it as playback device on the Spotify app, and it would take multiple attempts to connect to the speaker. After it is connected it will sometimes forget that the playback device is my google home mini. On the google home app it also doesn't show that the music is coming from Spotify. Thus, when I go to skip songs it'll playback on my phone and cut the stream on the google mini because I'm playing it on another device.
Thanks for reaching out. I know how it feels when something isn’t working the way it should, let's see what I can do to help. A few questions:
Could you try rebooting your speakers and router for a minute to refresh the connection?