Problem getting User Information with Oauth and AzureAD

Hi

I'm trying to use Azure AD as an Oauth IDP on our F5. I followed the LAB in https://clouddocs.f5.com/training/community/iam/html/class6/lab4.html and authentication works without any Problems. But i need to pass the User Email Address to the Backend after succesfull Authentication. As there is no Session Variable holding the Email-Address, how can we query for that Info after succesfull authenticatoin? As i'm very new to Oauth, a Dummy-Explanation would be realy helpful!

Thanks

Sbu