Hello jkufabulous,
If there's another account linked that you want to remove, you can use these steps:
1. On your iPhone, iPad, or Android device, open the Google Home app.
2. Tap Settings.
3. Tap Music.
4. Under Apple Music, tap Unlink. If Apple Music is set as your default music service, select another music service as your default, or select "No default." Then tap Unlink under Apple Music.
To link the account you want to use with the Google device, use these steps:
1. On your iPhone, iPad, or Android device, open the Google Home app.
2. Tap Settings.
3. Tap Music.
4. Under "More music services," tap the Link icon
next to Apple Music.
5. Tap Link Account.
6. Sign in with the Apple ID that you use with Apple Music and follow the onscreen steps to complete setup.
Once the account is linked and set up, you can then make your request on the device by saying "Hey Google" then "Play Song/Artist/Album/Genre/etc."
Play Apple Music on your Google Nest speaker or display
Listen to music on speakers and displays
Cheers!