Hi @Mansi Vaishnav ,
This is expected behavior if Assignment Required is set to "Yes", but admin consent was not provided.
This is documented in the Requesting not authorized permissions error documentation:
Another scenario in which this error might occur is when the user assignment is required for the application, but no administrator consent was provided. In this case, the administrator must first provide administrator consent.
To resolve this you would need to make sure the admin provides admin consent and there isn't currently another workaround.
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