the it created 2 customs fields in a field_header : 

{

    "asset_type_fields": "

        {

 "field_header": "DigitalTwin",

            "fields":

                {

                    "id": 21013902627,

                    "created_at": "2024-10-15T15:38:41Z",

                    "updated_at": "2024-10-15T16:25:21Z",

                    "asset_type_id": 21002953778,

                    "name": "managed_21002953778",

                    "label": "managed",

                    "required": false,

                    "is_unique": false,

                    "field_type": "checkbox",

                    "data_type": "boolean",

                    "default_field": false

                },

                {

                    "id": 21013902628,

                    "created_at": "2024-10-15T16:29:07Z",

                    "updated_at": "2024-10-15T16:29:07Z",

                    "asset_type_id": 21002953778,

                    "name": "unity_id_21002953778",

                    "label": "unity_id",

                    "required": true,

                    "is_unique": false,

                    "field_type": "text",

                    "data_type": "string",

                    "default_field": false

                }

            ]

        }

}  if i use that in the body of my post request to create a new asset 

  { "asset_type_fields": t

{

    "field_header": "DigitalTwin",  // This header might need to specify the context

    "fields": {

        "unity_id_21002953778": "5737f105-4c64-4382-b343-a05269149d10-0035519c",

        "managed_21002953778": true

    }

}

   ]

  } i have the error that i cannot have an empty asset_type_id. I was expecting that cause it s mandatory. Now the question! where do i add the field asset_type_id ?? if i just add it i have a message that my fields and header_field are now invalid field!!