Verizon now makes it possible for customers to defend against SIM swapping attacks by enabling the free Number Lock protection feature. SIM swapping (aka SIM hijacking, or SIM jacking) is a type of account takeover (ATO) fraud that allows criminals to take control of a target’s phone number. T-Mobile, Sprint, and AT&T aren’t yet providing a similar feature for their customers as Vice reported. The Federal Bureau of Investigation (FBI) issued a SIM swapping alert in 2019 with protection guidance after noticing an increase in the number of SIM swap attacks.
Source: https://www.bleepingcomputer.com/news/security/how-to-protect-your-verizon-number-from-sim-swapping-attacks/