Hi @Neel Patel ,
Unknown Errors: The unknown errors could be due to various reasons such as network issues, API rate limits, or specific file conditions. It might be helpful to check the error codes and messages returned by the API to get more insights.
Execution Time: The longer execution time for files that already have a label could be due to the additional processing required to update the existing label.
There is currently no other sensitivity label graph Api that performs faster. Personally, I completely agree with you, this is indeed a good addition to the current features of SharePoint. Thank you for bringing things to our attention. We sincerely recommend you go to SharePoint Feedback community to provide your feedback: SharePoint · Community (microsoft.com).
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