No ChannelData except message text while receiving incoming message from Skype in Bot Framework

When I'm receiving the message from Telegram, I get detailed information about account in Activity.ChannelData field (such as username, conversation_id and so on).

{
  "update_id": ,
  "callback_query": {
    "id": "",
    "from": {
      "id": ,
      "is_bot": false,
      "first_name": "",
      "last_name": "",
      "username": "",
      "language_code": ""
    },
    "message": {
      "message_id": ,
      "from": {
        "id": ,
        "is_bot": true,
        "first_name": "",
        "username": ""
      },
      "chat": {
        "id": ,
        "first_name": "",
        "last_name": "",
        "username": "",
        "type": "private"
      },
      "date": ,
      "text": "Example text"
    },
    "chat_instance": "",
    "data": ""
  }
}

But when it comes to Skype, all I see is the message text and nothing else.

{  "text": "Example text"}

How to know out, who exatly sent me the message?

Upd: That should not be exactly the user's name, any additional data like user unique id would fit.