Google home won't play audio on its own speaker

Hoping for help with my google home. It's linked to a Spotify premium family plan. The plan is owned by person A. Person A has an iPhone.

Person B has a google pixel. When person B tells google home to play a song google says "ok, playing on apple music" and plays the song on person A's phone. This happens whether person A is home or not.

According to Google home settings the default music player is the Spotify premium account.

Can anyone help us get Google home to play music on its own speaker?