How do you iterate a subarray in json?

[Lightningblade]

json input

{
    "tag": "CARL A",
    "isin": "DK0010181676",
    "shares": 33699252,
    "name": "Carlsberg Breweries A/S",
    "url": "https://www.carlsberggroup.com/",
    "market": "Nasdaq Copenhagen",
    "sector": "Food, Beverage and Tobacco",
    "segment": "Large",
    "trades": [
        {
            "time": "2012-10-31T08:01:00Z",
            "price": 527,
            "amount": 35,
            "buyer": "DDB",
            "seller": "NDA",
            "seq": 1,
            "code": 0
        },
        {
            "time": "2012-10-31T08:30:00Z",
            "price": 512,
            "amount": 100,
            "buyer": "DDB",
            "seller": "DDB",
            "seq": 2,
            "code": 0
        }
    ]
}

Accessing the trades gives me as expected:

[
    {
        "amount": 35,
        "buyer": "DDB",
        "code": 0,
        "price": 527,
        "seller": "NDA",
        "seq": 1,
        "time": "2012-10-31T08:01:00Z"
    },
    {
        "amount": 100,
        "buyer": "DDB",
        "code": 0,
        "price": 512,
        "seller": "DDB",
        "seq": 2,
        "time": "2012-10-31T08:30:00Z"
    }
]

However iterating over j["trades"] via for (auto &trade : jsontrades) loops once with

{
    "amount": 35,
    "buyer": "DDB",
    "code": 0,
    "price": 527,
    "seller": "NDA",
    "seq": 1,
    "time": "2012-10-31T08:01:00Z"
}

and null together with an error:

terminate called after throwing an instance of 'nlohmann::detail::type_error'
  what():  [json.exception.type_error.302] type must be string, but is null

What am I doing wrong?

[gregmarr]

Answered in another thread, string in code didn't match value name in JSON.