Customers of T-Mobile recently received the following text message that some people thought was a scam, but was entirely legitimate. The text message read, “T-Mobile Alert: We have identified an industry-wide phone number port out scam and encourage you to add account security.” A port out scam occurs when a scammer contacts your mobile carrier and convinces them to change your phone number to a new phone controlled by the scammer. This enables the scammer to move on to scams such as taking over bank accounts that may be tied to your phone for security purposes through dual factor authentication. With dual factor authentication, whenever you are going to access an online account, a special code is sent to your smartphone after you have typed in your user name and password. However, if the scammer has taken control of your phone, he or she is able to defeat dual factor authentication. I have been warning you about this type of scam for five years and it is becoming more serious.
More and more, scammers are contacting mobile providers and tricking customer service into changing the SIM card of targeted victims to one in a phone controlled by the hackers. A Subscriber Identity Module, more commonly known as a SIM card, is an integrated circuit that stores information including your smartphone number and is used to authenticate subscribers on mobile devices.  The SIM card is able to be transferred between different devices, and often is, when people update into a newer smartphone.  
TIPS
Fortunately, there is an easy way to enhance your security to protect your SIM card from being switched thereby thwarting the protections provided by dual factor authentication and that is to set up a PIN or password to be used for access to your mobile service provider account.  Sprint and Verizon use PINs while T-Mobile and AT&T will let you set up a password. If you are a T-Mobile customer, you click on this link to add a password to your account to be used in order to take steps such as changing a SIM card. https://www.t-mobile.com/customers/secure 
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