Return to work notifications is not firing

Summary:

Content (required):

Hi Expert,

When an employee completes a sickness absence, it should send a notification to their line manager, prompting them to complete a Return to Work. This is not happening. There is an employee who has completed his sickness absence 5 days ago but no RTW notification has been received by the line manager.

Please suggest something, if anyone has faced this issue before.

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):