Google has made phone number verification on Android an opt-out rather than an opt-in feature. This change automatically links a device's phone number to every Google account signed in on that phone. Users have started receiving unexpected confirmation emails about this automatic verification. This means your primary phone number is now associated with secondary, work, and disposable Google accounts on your device. Google's support documentation was updated to reflect this new default behavior. To disable automatic verification, navigate to Settings > Google > All Services > Privacy & Security > Phone number verification and turn off the toggle. Disabling the toggle only stops future linking of your number. If your number has already been linked to other accounts, you must manually remove it from each profile. This is done through your Google Account's Personal Info page under Contact info > Phone. Users need to be aware of this change to manage their privacy settings effectively.