In 2022, T-Mobile stripped customers of the ability to change SIM cards on their own. The company said it was a temporary measure to beef up security but it took a lot longer than expected to re-enable the feature.T-Mobile disabled self-service SIM swaps to prevent SIM hijacking or SIM swap attacks. These unauthorized SIM changes occur when a criminal transfers your number to a SIM card they own by using unlawful tactics, such as bribing employees. Since phone numbers are often associated with bank accounts and social media profiles, SIM swap attacks allow criminals to drain the victim's accounts by accessing two-factor authentication (2FA) verification codes and trick their friends and family into giving them money.T-Mobile wanted to implement extra security features before allowing customers to swap their own SIMs or change the SIM attached to their number. And even as we saw the company put morechecks in place, there was no sign of self-service SIM swaps returning until today. This was irritating, as after the deactivation of online and in-app SIM swaps, customers were required to contact customer service representatives or visit a store to do a SIM swap or activate eSIM. All this while, AT&T and Verizon customers were able to do SIM swaps, so it's not clear what took T-Mobile so long. The company probably didn't want to risk another costly arbitration award.