Missing EventMessageDetail's

Question

Hi there,

I am currently working with the Graph API to pull Teams messages, there are a number of issues with the data that I have spotted and would like some extra eyes on to verify that it's doing what it's supposed to be doing. I am trying to gather more information about when calls started, ended and the call ID's, so I can do some further processing on that particular call.

Channel parent messages seem to not contain any call ID when the payload is returned, the system message just states the call/meeting began at as specific time and that is all, further more there is no system message that states when the call/meeting ended. See the example payload below:

{  
  "attachments": [],  
  "body": {  
    "content": "<systemEventMessage/>",  
    "contentType": "Html"  
  },  
  "channelIdentity": {  
    "channelId": "--redacted--",  
    "teamId": "--redacted--"  
  },  
  "createdDateTime": "2022-03-11T00:06:58.297+00:00",  
  "etag": "1646957874099",  
  "eventDetail": {  
    "callEventType": "Meeting",  
    "callId": null,  
    "initiator": {  
      "user": {  
        "id": "--redacted--",  
        "userIdentityType": "aadUser"  
      }  
    },  
    "@odata.type": "#microsoft.graph.callStartedEventMessageDetail"  
  },  
  "importance": "Normal",  
  "lastModifiedDateTime": "2022-03-11T00:17:54.099+00:00",  
  "locale": "en-us",  
  "mentions": [],  
  "messageType": "UnknownFutureValue",  
  "reactions": [],  
  "webUrl": "--redacted--",  
  "id": "1646957218297",  
  "@odata.type": "#microsoft.graph.chatMessage"  
}  

1. Notice the message type is "UnknownFutureValue", this is common throughout all "system messages", none of them I have received have had the correct relevant type assigned. Is this a known issue?
2. Call ID of null makes me think that the call has not been full started or something and hadn't had an ID assigned yet, however the messages I am looking at are relatively old and would have had those fields populated by now, so I'm not sure why ID's wouldn't be present in payloads, any ideas?

Notes,

• I have all the upper access to those resources via Application level access
• Using API Resource as reference - https://learn.microsoft.com/en-us/graph/system-messages
• Fetching ChatMessage resources via endpoint - https://learn.microsoft.com/en-us/graph/api/channel-list-messages?view=graph-rest-1.0&tabs=http
• Using Official Graph C# Microsoft.Graph Client