Overview
The "University of Idaho" Enterprise Workspace in ClickUp uses SSO for authentication. If an existing non-SSO account is being used, the account will initially need to sign-in with the non-SSO credentials and then "Sign in with Microsoft". Here is what the process looks like.
Sign-in
Access the University of Idaho Enterprise Workspace at https://uidaho.clickup.com/.
If you click on the "Continue with SSO" it will display an error.

SSO is not linked for this email, please login without SSO

Select "Continue without SSO" and use the ClickUp credentials to sign-in. You will then be presented with the option "Sign in with Microsoft".

The standard University of Idaho SSO will be displayed in a pop-up window.

After this initial sign-in, you will be able to use the option "Continue with SSO" in the future.