Hello Harmeet Singh,If you’re using Graph Explorer, make sure you have signed in with the correct account type and have the necessary permissions granted to your user account.
Ensure that you’re using the correct permission type. For delegated permissions, OnlineMeetings.Read should be consented in Modify Permissions Tab to use onlinemeetings Graph API.
Please check below screenshots:
If you need to get response after consenting required permissions, then you need to pass 'meetingid' in Graph API call.
GET https://graph.microsoft.com/v1.0/me/onlineMeetings/{meetingid}
Please refer to documentation. https://learn.microsoft.com/en-us/graph/api/onlinemeeting-get?view=graph-rest-1.0&tabs=http
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