<ul data-eligibleForWebStory="true">AT&T has launched a new Account Lock feature to protect users from SIM swapping attacks.SIM swapping attacks involve unauthorized changes to accounts, allowing attackers to intercept messages and break into sensitive accounts.Other carriers like T-Mobile, Verizon, and Google Fi already offer similar features to prevent such fraud.The Account Lock feature by AT&T also blocks device upgrades and changes to authorized users and phone numbers.