security code and my outlook.com e-mail account

When I try to log on to my outlook e-mail account the system says I need a security code because I have access to "sensitive" material. I don't know what that means. I am a retired widower with no need to access "sensitive" material. I have had this account for ten year.. This has happened three or four times. But when I get the security code the system won't accept it. Finally it allows me to log in with my password but it warns that I will be subjected to this procedure again in a few days. I am afraid I will be blocked from my e-mail account. Please help me avoid this extra obstacle to my log in and to avoid being blocked from my account.]

please respond to *** Email address is removed for privacy ***. Thank you