Auto complete rule on warning isn't getting triggered in Request New Position Transaction

Summary: We have created an autocomplete rule which will trigger a warning when either "Union or Bargining Unit" isnt filled while requesting a new position. But we are seeing weird behavior and unable to see any pattern how the system throws the warning. in most cases the auto complete rule isn't getting fired.

Content (please ensure you mask any confidential information): Have sent all the details. If anyone has worked on warnings and faced this , kindly throw some light here.

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

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