I've been facing issues while integrating OnlineMeeting scope from Microsoft's Graph API for many days and have explained my issue below in detail:
I've inserted these scope[ OnlineMeetings.Read and OnlineMeetings.ReadWrite ] in my App Registration in API permissions in Azure Platform for generating Access Tokens through Oauth Flow.
After that, I've added that into the Expose an API section tab in Azure Platform.
I've coded the logic in PHP and then after I've passed the scopes in the URL section for generating Oauth code and after there, took the code from URL and processed it ahead for generating access tokens along with refresh and scopes valid for the tokens.
After that, the tokens are received from the curl are working fine for Calendar, email, profile but not for OnlineMeeting scope as this particular scope is not shown in the response of it. See this.
If these access tokens are used for OnlineMeeting create API then I would get the 400 error for Bad request. See this
Would be great if anyone who has gone through this, would come forward and help me out!