Spotify shuffle has three states: not shuffled, shuffled, smart shuffled. The third option will let Spotify recommend and add songs to your queue and playlist.
However, Sonos only have two. When enabling shuffling on Sonos, it will actually enable smart shuffle on Spotify, leading to unwanted songs in my playlist.
A current workaround is just disconnect and revoke spotify approval to sonos. I think it’s the problem from Sonos side.