If you see the message that your connector's authentication is no longer valid, this means that Keepit cannot perform a backup and your health status is critical.
The most common reason this happens is because your authentication gets expired or revoked. In that case, Keepit loses connection with your SaaS application.
To renew the authentication, simply reauthenticate your connector. You can do this by clicking "reauthenticate" on your connector's status, either from the Connector's page or the Dashboard.