Swift 3 alamofire swiftyjson subscript - ios

Question

I don't know why my code doesn't work, my result is always nil.
I integrated alamofire and swiftyjson this is my code:
let urlString = "myurl"
let params: Parameters = [
"accessProvider": AccessProvider,
"inputToken": AccessToken
]
Alamofire.request(urlString, method: .post, parameters: params, encoding: URLEncoding.httpBody)
.responseJSON { response in
if let responseObject = response.result.value {
print("JSON: \(responseObject)")
let json = JSON(responseObject)
let path: [JSONSubscriptType] = ["user","id"]
let name = json[path].string
print("AAAAA")
print(name)
}
}
I can read the first part of user but the second one with id is always nil.
this is the response json:
{
"responseCode": 0,
"responseDescription": "OK",
"user": "{"id":"MAIL",
"nickname":"MYNAME",
"level":"U",
"status":"A",
"sex":null,
"ageGroup":null,
"address":null,
"latitude":null,
"longitude":null,
"creation_timestamp":"2017-05-10 18:40:21",
"notification":"1",
"last_login":"2017-05-11 18:32:07",
"mobilePreference":null,
"sport":null,
"spot":null,
"token":"LONGTOKENID"}"
}

Answer 1

Thank you vadian,
i solved the question with your indication,
if anyone have the same problem you can solve like this:
//Initialize the first json:
let json = JSON(responseObject)
//Extract the second Json to String
let path: [JSONSubscriptType] = ["user"]
let name = json[path].string
//Initialize the second json from string
if let dataFromString = name?.data(using: .utf8, allowLossyConversion: false)
let jsonuser = JSON(data: dataFromString)
//Access to the data
Thank you all,
Have nice day.