Adaptive card not visible in preview mode in a Channel

Question

Hey there team, recently I have noticed that if I try to send an adaptive card like this one to a private chat the preview works but in a channel, the preview is broken

{
    "composeExtension": {
        "attachments": [
            {
                "content": {
                    "type": "AdaptiveCard",
                    "body": [
                        {
                            "columns": [
                                {
                                    "width": "auto",
                                    "items": [
                                        {
                                            "horizontalAlignment": null,
                                            "size": "small",
                                            "style": null,
                                            "url": "https://eu-prod.asyncgw.teams.microsoft.com/urlp/v1/url/content?url=https%3a%2f%2fapp.test.com%2fdist%2fimg%2ficons%2femails%2fsession.png",
                                            "width": "14px",
                                            "height": "14px",
                                            "separator": false,
                                            "type": "Image"
                                        }
                                    ],
                                    "separator": false,
                                    "type": "Column"
                                },
                                {
                                    "width": "stretch",
                                    "items": [
                                        {
                                            "color": "accent",
                                            "horizontalAlignment": null,
                                            "isSubtle": false,
                                            "maxLines": 0,
                                            "size": "small",
                                            "text": "[Session: Q4 2021]",
                                            "weight": null,
                                            "wrap": true,
                                            "separator": false,
                                            "type": "TextBlock"
                                        }
                                    ],
                                    "separator": false,
                                    "type": "Column"
                                }
                            ],
                            "separator": false,
                            "type": "ColumnSet"
                        },
                        {
                            "columns": [
                                {
                                    "width": "auto",
                                    "items": [
                                        {
                                            "horizontalAlignment": null,
                                            "size": "small",
                                            "style": null,
                                            "url": "https://eu-prod.asyncgw.teams.microsoft.com/urlp/v1/url/content?url=https%3a%2f%2fapp.test.com%2fdist%2fimg%2ficons%2femails%2fobjective.png",
                                            "width": "14px",
                                            "height": "14px",
                                            "separator": false,
                                            "type": "Image"
                                        }
                                    ],
                                    "separator": false,
                                    "type": "Column"
                                },
                                {
                                    "width": "stretch",
                                    "items": [
                                        {
                                            "color": "accent",
                                            "horizontalAlignment": null,
                                            "isSubtle": false,
                                            "maxLines": 0,
                                            "size": null,
                                            "text": "[Objective: asd _(0%)_]",
                                            "weight": null,
                                            "wrap": true,
                                            "separator": false,
                                            "type": "TextBlock"
                                        }
                                    ],
                                    "separator": false,
                                    "type": "Column"
                                }
                            ],
                            "style": "default",
                            "spacing": "Small",
                            "separator": false,
                            "type": "ColumnSet"
                        }
                    ],
                    "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
                    "version": "1.0"
                },
                "contentType": "application/vnd.microsoft.card.adaptive",
                "preview": {
                    "content": {
                        "title": "asd",
                        "text": "k b",
                        "images": [
                            {
                                "url": "https://eu-prod.asyncgw.teams.microsoft.com/urlp/v1/url/content?url=https%3a%2f%2fapp.test.com%2fdist%2fimg%2ficons%2femails%2fobjective.png"
                            }
                        ]
                    },
                    "contentType": "application/vnd.microsoft.card.thumbnail"
                }
            }
        ],
        "type": "result",
        "attachmentLayout": "list"
    },
    "responseType": "composeExtension"
}