Teams adaptive card, unable to reach app

I get the unable to reach app error when i try to submit my adaptive card form.

The card is posted to a team using power automate.

My json:

{
    "type": "AdaptiveCard",
    "body": [
        {
            "type": "TextBlock",
            "text": "Naam van project",
            "wrap": true
        },
        {
            "type": "ColumnSet",
            "columns": [
                {
                    "type": "Column",
                    "width": "stretch",
                    "items": [
                        {
                            "type": "Input.Text",
                            "placeholder": "Placeholder text",
                            "id": "1"
                        }
                    ]
                }
            ]
        },
        {
            "type": "TextBlock",
            "text": "Team",
            "wrap": true,
            "id": "2"
        },
        {
            "type": "Input.ChoiceSet",
            "choices": [
                {
                    "title": "ProAV",
                    "value": "ProAV"
                },
                {
                    "title": "Media",
                    "value": "Media"
                },
                {
                    "title": "Producties",
                    "value": "Producties"
                }
            ],
            "placeholder": "Producties",
            "id": "3"
        },
        {
            "type": "ActionSet",
            "actions": [
                {
                    "type": "Action.Submit",
                    "id": "5",
                    "title": "MAAK"
                }
            ]
        }
    ],
    "$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
    "version": "1.4"
}