Automatically Updating Candidate Status When Documents Expire
This setting allows you to automatically update a candidate’s profile status when any of their documents expire. You can choose the new status by selecting from the 'Status to set to' dropdown, which includes all available candidate profile statuses.
1- Open any candidate profile (this setting is global and will be reflected for all candidates)
2- Navigate to the "Documents" sections and click on the gear icon.

3- Enable the setting "If any document of a candidate expires, set candidate to a status"
4- Select the relevant status from the drop-down.

You may also find the following article helpful:
How to send email notifications to candidates and admins when documents are expiring