@Haroon Rasheed Thanks for posting in our Q&A.
UnknownError is a very general error code. We usually try to troubleshoot it based on the specific request.
Graph issue is more related to develop scope. With Q&A limitation resource, it is suggested to create a Premier or Unified support ticket to get more help. Here is the support link:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for your understanding.
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