Try this...
From your iPhone, iPad, or computer running macOS, locate the Home app.
- Tap the Home app icon to open the app
- Locate the room where your HomePod is located
- Press and hold on the HomePod's icon to access settings
- Tap the gear icon at the bottom of the first page to enter Settings
- Scroll to 'Music & Podcasts" and tap on "Primary User"
- Tap on the person to select as the Primary User
- In the "HomePod Account" settings, note which user is logged in.
- Tap "Sign Out" to change the user account to be associated with this HomePod.
- OR
- Tap "Sign In" to assign an AppleID for Siri to use with this HomePod.
NOTE: The Primary User and the AppleID do not have to the same.