HTTP POST request to incoming webhook with valid adaptive card json payload returns a 200 with error

Keerthi_sh2085 , In the provided JSON the TextRun elements have empty text properties. This might cause issues. Also, many elements have isVisible set to false. The ActionSet elements have empty actions arrays. 

Below updated JSON works properly:

{
  "type": "message",
  "attachments": [
    {
      "contentType": "application/vnd.microsoft.card.adaptive",
      "contentUrl": null,
      "content": {
        "$schema": "https://adaptivecards.io/schemas/adaptive-card.json",
        "type": "AdaptiveCard",
        "version": "1.2",
        "msteams": {
          "width": "Full"
        },
        "body": [
          {
            "type": "Container",
            "bleed": false,
            "minHeight": "0px",
            "style": "default",
            "verticalContentAlignment": "center",
            "items": [
              {
                "type": "TextBlock",
                "size": "large",
                "style": "heading",
                "wrap": true,
                "text": "Heading Text"
              }
            ]
          },
          {
            "type": "ColumnSet",
            "columns": [
              {
                "type": "Column",
                "items": [
                  {
                    "type": "RichTextBlock",
                    "inlines": [
                      {
                        "type": "TextRun",
                        "text": "Status: ",
                        "wrap": true,
                        "fontType": "monospace"
                      },
                      {
                        "type": "TextRun",
                        "text": "Active",
                        "wrap": true,
                        "color": "default",
                        "weight": "bolder",
                        "fontType": "monospace"
                      }
                    ]
                  }
                ]
              },
              {
                "type": "Column",
                "items": [
                  {
                    "type": "RichTextBlock",
                    "inlines": [
                      {
                        "type": "TextRun",
                        "text": "Actor: ",
                        "wrap": true,
                        "fontType": "monospace"
                      },
                      {
                        "type": "TextRun",
                        "text": "John Doe",
                        "wrap": true,
                        "size": "medium"
                      }
                    ]
                  }
                ]
              }
            ]
          },
          {
            "type": "ColumnSet",
            "columns": [
              {
                "type": "Column",
                "width": "stretch",
                "style": "emphasis",
                "minHeight": "40px",
                "items": [
                  {
                    "type": "TextBlock",
                    "text": "The minimal message!",
                    "wrap": true
                  }
                ]
              }
            ]
          }
        ]
      }
    }
  ]
}

 Result:

Thanks, 

Prasad Das

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Keerthi_sh2085 - Apologies. Currently we don't have any exact ETA to share. Engineering team is investigating the issue, and we will inform you once we have any update. Thanks!