Desktop Outlook will not allow me to add account. But my iPhone and Web app work fine

My work email was working fine on my desktop outlook app. For some reason, my desktop outlook app stopped allowing me to access my work email. My iPhone outlook app and the web outlook still work and allow me to access my work email. I tried hitting the refresh button on my work email. It did nothing. I tried erasing the account and reinstalling it. I get this error message "your organization does not allow adding personal accounts in Outlook" Now I can only access my work email from my phone or the web application. I am scared of losing that access by erasing it totally from my web and iPhone. How can I fix this?