Named Credential: ClosePlan Metadata Service is part of ClosePlan configuration and must be authenticated by an active user in the organization.
If a User is inactive, the configuration will break and will need to be re-authenticated by another active user.
Example: If the User leaves the company.
How to Re-Authenticate Credentials:
Go to Setup > into the quick find box enter Named Credentials.
Open ClosePlan Metadata Service > click Edit
Disable Start Authentication Flow on Save and Save