The error code 'AF20024' for the Office 365 Management API is not in the documentation.
I think you should mention it, because it can happens.
https://learn.microsoft.com/en-us/office/office-365-management-api/office-365-management-activity-api-reference#errors

proposed change
Add to the file 'office-365-management-activity-api-reference.md' the following line in the markdown table:
|AF20024|The subscription is already enabled. No property change.|