Some of the entities are not applicable for auditing for example : Case Suggestion, Category, chatbot etc. For reference please find the screenshot and follow it.
Once you click on that it will be navigate to you entity area see the below screen.
Now see the Audit Status column some the entity is having enable, disable status but some of the entity is having not applicable status.
We can only audit entity which is having enable or disable status but we can’t do anything with Not Applicable.
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