Right and wrong Nimble API request

right_request.json

{
    "fields": {
       "last name": [{
            "value": "jack",
            "modifier": ""
        }],
        "first name": [{
            "value": "Jsssack",
            "modifier": ""
        }]
    },
    "type": "person"
}

wrong_request.json

{
    "fields": {
        "last name": {
            "value": "jack",
            "modifier": ""
        },
        "first name": {
            "value": "Jsssack",
            "modifier": ""
        }
    },
    "type": "person"
}