A Microsoft file hosting and synchronization service.
Hi Niraj Bagde,
Thank you for contacting Microsoft!
The 503 (Service Unavailable) and 429 (Too Many Requests) errors indicate that the client application has been throttled, and the request needs to be retried after a delay.
To help mitigate this, please refer to the following best practices for handling throttling:
https://learn.microsoft.com/en-us/graph/throttling#best-practices-to-avoid-throttling
https://learn.microsoft.com/en-us/graph/throttling-limits#outlook-service-limits
Hope this helps.
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