Your Phone Number is Your Enemy
If you still use SMS text messages as a two-factor authentication method on your exchange, you are in serious danger
There is a technique called SIM Swapping where hackers deceive your phone company to duplicate your SIM card. At that moment, they receive your security codes and can access your account and change the password.
Eliminate SMS verification today and switch to authentication apps like Google Authenticator or Authy that generate local codes on your device and do not depend on your phone line.
It is a 2-minute configuration change that secures your account against one of the most common attacks in the world