If you are not on campus you will need to connect to the VPN to be able to reach the Software Center.
First Close all Office Apps (Teams, Outlook, Word Excel, etc...)
Click on the Start or Search buttons in the lower-left corner and type Software Center.
Software Center
Click Software Center to launch the program.
Software Center
Click Applications then select Office Auth Fix
Click Install.
You can also use the Search bar to find the application.
If you still have trouble after the install finishes, restart your computer.