This can happen on any site that uses Passport as the login system or the portal when your browser has been open for a long time (many days).

Clearing the cache and cookies may not work.

The solution is to close the browser then reopen it; or if you really don't want to do that, use a different browser or different computer.

For issues with Passport log ins, you can contact the Office of Information Technology. You can find information about how to contact them here: https://www1.ucdenver.edu/offices/office-of-information-technology/get-help