Hi @Muhammad Usman shaikh · Thank you for reaching out.
As of now you can NOT use the access token received by using Azure AD B2C user flow or custom policy to call Graph API. This is because Azure AD B2C tenant doesn't include same set of Delegated Permissions for Graph API that you get with Standard Azure AD tenant. The only delegated permissions for Graph API are shown below:
You can post a feedback regarding this feature in our Feedback Portal.
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