I'm trying to port API code from ExchangeService to Microsoft Graph for handling meeting requests received in a mailbox.
The old code casts inbox messages as MeetingMessage and then refers to the appointment by its item.AssociatedAppointmentId.UniqueId. MS Graph doesn't seem to have a similar id in its message properties?
I get the meeting messages from the Inbox with
var inboxMessages = await graphClient.MailFolders.Inbox.Messages.Request().GetAsync();.
I tried https://graph.microsoft.com/v1.0/users/[mail]/mailFolders/Inbox/messages/[message_id]?$expand=microsoft.graph.eventMessage/event, but it returns "404 The resource was not found".
How do you get the appointment id from the meeting request message in MS Graph?