I have same issues with my azure devops post call
POST: https://dev.azure.com/$organization/$project/\_apis/test/Runs/$runID/results?api-version=7.1-preview.3

Body:

{
    "results":[
                {"durationInMs":469.0,"automatedTestType":"UnitTest","testCase":{"id":2233},"state":"Completed","outcome":"Passed","automatedTestName":"[TC-2233]My_Login.","automatedTestStorage":"MYTest.postman_collection.json"},
                {"durationInMs":384.0,"automatedTestType":"UnitTest","testCase":{"id":3240},"state":"Completed","outcome":"Passed","automatedTestName":"[TC-3240] My_Alerts","automatedTestStorage":"MYTest.postman_collection.json"}
            ]
}

But Response Body: 400 bad request

{
    "$id": "1",
    "innerException": null,
    "message": "Value cannot be null.\r\nParameter name: resultCreateModel",
    "typeName": "System.ArgumentNullException, mscorlib",
    "typeKey": "ArgumentNullException",
    "errorCode": 0,
    "eventId": 0
}

Can someone help me with this