title: Webhook call failed. Error: Failed to parse webhook JSON response: Cannot find field: ETag in message
body: <p>I'm trying to send a repsonse from my webapp back to dialogflow but get the following error</p>
  
  <blockquote>
    <p>"Webhook call failed. Error: Failed to parse webhook JSON response:
    Cannot find field: ETag in message
    google.cloud.dialogflow.v2beta1.WebhookResponse."</p>
  </blockquote>
  
  <p>This is my code</p>
  
  <pre><code>public class HomeController : Controller
  {
      [HttpPost]
      public string Index(GoogleCloudDialogflowV2WebhookRequest obj)
      {
          var response = new GoogleCloudDialogflowV2WebhookResponse();
          response.FulfillmentText = "Hello world";
          var output = JsonConvert.SerializeObject(response);
          return output; ;
      }
  }
  </code></pre>
  
  <p>this is the json I return</p>
  
  <pre><code>{  
     "followupEventInput":null,
     "fulfillmentMessages":null,
     "fulfillmentText":"lee",
     "outputContexts":null,
     "payload":null,
     "source":null,
     "ETag":null
  } 
  </code></pre>
  
  <p>Any ideas? I'm using using </p>
  
  <blockquote>
    <p>Google.Apis.Dialogflow.v2.Data;</p>
  </blockquote>