Google's Background 'Automatic Phone Number Verification' Triggers Multi-Account Linking? 2026 Guide to Unlinking Google Accounts and Secure SMS Verif

The 'Verify phone numbers automatically' feature, enabled by default on Android, silently links your SIM card number to all Google accounts on the device, breaking account isolation and causing cascading risk controls and international SMS charges. This article explains how to disable automatic verification, clean up linked numbers, and use NexSMS to configure independent SMS verification for each account.