'NSInvalidArgumentException'，原因：“ JSON写入（_SwiftValue）中的类型无效”

Question

let params:[String : Any] = ["mobileNumber": mobileNumberTextField.text!,
                             "password": byteArrayPassword]

Alamofire.request(url, method: .post, parameters: params,encoding: JSONEncoding.default, headers: headers).responseJSON {
       response in
   switch response.result {
   case .success:
      print(response)
      break
   case .failure(let error):
      print(error)
   }
}

此查询中我做错了什么？