How do troubleshoot warning messages on Alerts from Alert log

Summary:

Learning Alerts delivered by oracle were configured for the client and is working as expected. However, some New course assignment runs are completing in warning. This means some of the employees have not recieved the courses and we want to troubleshoot further to understand who didn't recieve the new course alert.

Has anyone done this before or have a query that looks at the alerts table and helps us retrieve this info?

Content (required):

Troubleshooting warning and error messages in Alerts log

Version (include the version you are using, if applicable): 23B

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