title: Action.Submit on Adaptive Cards not working with Input.Text Python SDK
body: <p>I am trying the adaptive cards with the Bot Builder v4 Python SDK. I am trying to gather feedback from the user using the Input.text field and then the Action.submit </p>
  
  <pre><code>{
  "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
  "type": "AdaptiveCard",
  "version": "1.0",
  "body": [                           
  ],
  "actions": [{
          "type": "Action.ShowCard",
          "title": "Want to provide feedback",
          "card": {
              "type": "AdaptiveCard",
              "actions": [
          {
              "type": "Action.Submit",
              "data": "Yes, it was helpful",
              "title": "Yes"
          },
          {
              "type": "Action.Submit",
              "data": "No, it wasn't helpful",
              "title": "No"
          },
          {
              "type": "Action.Submit",
              "data": "Start Over",
              "title": "Start Over"
          },
          {
              "type": "Action.Submit",
              "data": "Exit",
              "title": "Exit"
          },{
          "type": "Action.ShowCard",
          "title": "Comment",
          "card": {
              "type": "AdaptiveCard",
              "body": [
                  {
                      "type": "Input.Text",
                      "id": "comment",
                      "isMultiline": true,
                      "placeholder": "Enter your comment"
                  }
              ],
              "actions": [
                  {
                      "type": "Action.Submit",
                      "title": "OK"
                  }
              ]
          }
      }
          ]
          }
      }
  ]}
  </code></pre>
  
  <p>This is working well on the <a href="http://adaptivecards.io/visualizer/index.html?hostApp=Bot%20Framework%20WebChat" rel="nofollow noreferrer">visualizer</a>. When I write some comments and and click on OK, this works on the visualizer but does not work in practice. It raises a 502 error.</p>
  
  <p>See below screenshot
  <a href="https://i.stack.imgur.com/1U6c8.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1U6c8.png" alt="Sample screenshot"></a></p>
  
  <p>I'm using the Bot Build v4 SDK for Python and testing this on Web Chat. It seems there is no issue on the Adaptive Card side of this, I suppose this has something to do with the Python SDK. Any pointers as to where the error might be ?</p>