Authorization_IdentityNotFound while calling https://graph.microsoft.com/v1.0/organization API

I want to call https://graph.microsoft.com/v1.0/organization API but when I write code to call it , it will returned error, I have get token using below code, it is worked for users API of Graph, but not working for organization api

B2BGraphClient.AccessToken = await authContext.AcquireTokenAsync("https://graph.microsoft.com/", credential).ConfigureAwait(false);  

I have checked it using Postman, when I have pass token generated using https://login.microsoftonline.com/common/oauth2/token this api, organization api returns correct output, but logically it is not possible in code to pass userid and password to api and get token, below is image of postman call

I want correct way to do this

https://stackoverflow.com/questions/66920474/authorization-identitynotfound-while-calling-https-graph-microsoft-com-v1-0-or April 02, 2021 at 10:01PM