title: LUIS Add Utterance in code JSON POST failing
body: <p>Following this example:</p>
  
  <p><a href="https://docs.microsoft.com/en-us/azure/cognitive-services/luis/luis-quickstart-cs-add-utterance" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/azure/cognitive-services/luis/luis-quickstart-cs-add-utterance</a></p>
  
  <p>I am trying to send an utterance to my LUIS App.
  It keeps on failing with this response message:</p>
  
  <pre><code>{
    "error": {
      "code": "BadArgument",
      "message": "Failed to parse example labeling objects. Parameter name: exampleLabelObjects"
    }
  }
  </code></pre>
  
  <p>My input body is:</p>
  
  <pre><code>{
    "text": "hi, what can I help you with?",
    "intentName": "Help",
    "entityLabels": []
  }
  </code></pre>
  
  <p>And according too the link if you send an utterance without any entity labels the above is correct.</p>
  
  <blockquote>
    <p>The entityLabels field is required. If you don't want to label any
    entities, provide an empty list as shown in the following example:</p>
  </blockquote>
  
  <pre><code>[
      {
          "text": "go to Seattle",
          "intentName": "BookFlight",
          "entityLabels": [
              {
                  "entityName": "Location::LocationTo",
                  "startCharIndex": 6,
                  "endCharIndex": 12
              }
          ]
      },
      {
          "text": "book a flight",
          "intentName": "BookFlight",
          "entityLabels": []
      }
  ]
  </code></pre>
  
  <p>The C# to build the object is as follows:</p>
  
  <pre><code>public class LUISUtterItem
      {
          public string utterances;
          public string text;
          public string intentName;
          public List&lt;exampleLabelObjects&gt; entityLabels;
  
      }
  
      public class exampleLabelObjects
      {
          public string entityName;
          public int startCharIndex;
          public int endCharIndex;
      }
  </code></pre>
  
  <p>I call it using:</p>
  
  <pre><code>LUISUtterItem itm = new LUISUtterItem(); 
  
              //itm.utterances = materialArray[1];
              itm.text = materialArray[1];
              itm.intentName = materialArray[2];
              itm.entityLabels = new List&lt;exampleLabelObjects&gt;();
  </code></pre>
  
  <p>I have also tried not including an "entityLabels" object, as well as a string list that just gets initiated with the same result.</p>
  
  <p>Any help will be appreciated.</p>