Spotify Connect Not working with echo dot when connected via mobile hotspot

[bliblabl]

I have an echo dot on my car, it is connected with the internet via mobile hotspot from my android Device. I can't control the music on echo dot via Spotify app on the android Device that is serving the hotspot. "Available devices" isn't shown in Spotify app.

Some songs Alexa doesn't recognize via speech command, so it would be useful to control the music via app.