Hi @Anonymous,
I confirmed my side but not find the same issue, you said the adaptive card is custom by yourself, I guess maybe there is some error with the adaptive card code, could you please try the following code?
{
"$schema": "http://adaptivecards.io/schemas/adaptive-card.json",
"type": "AdaptiveCard",
"version": "1.2",
"body": [
{
"type": "TextBlock",
"text": "Tell us about yourself",
"weight": "Bolder",
"size": "Medium"
},
{
"type": "TextBlock",
"text": "We just need a few more details to get you booked for the trip of a lifetime!",
"isSubtle": true,
"wrap": true
},
{
"type": "TextBlock",
"text": "Your name",
"wrap": true
},
{
"type": "Input.Text",
"id": "myName",
"placeholder": "Last, First",
"spacing": "None"
},
{
"type": "TextBlock",
"text": "Your email",
"wrap": true
},
{
"type": "Input.Text",
"id": "myEmail",
"placeholder": "youremail@example.com",
"style": "Email",
"spacing": "None"
},
{
"type": "TextBlock",
"text": "Phone Number"
},
{
"type": "Input.Text",
"id": "myTel",
"placeholder": "xxx.xxx.xxxx",
"style": "Tel",
"spacing": "None"
}
],
"actions": [
{
"type": "Action.Submit",
"title": "Submit"
}
]
}

Best Regards,
Community Support Team _ Lin Tu
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