Multiple Echo Dots with Family Plan

[Darth_Veda]

I have the family plan. My wife and I both have Google Pixel 3a phones and our own echo dots. I generally use my phone via bluetooth while driving. Whenever she plays Spotify to her dot it interrupts my music in the car and shows what's playing from her device. I have used the "forget device" on her dot three to four times a day for a week and it just keeps coming back. We are signed into the family plan with different logins, using separate Amazon logins for our alexa accounts but this problem persists. Any suggestions??