获取错误不支持的授权类型？

Question

我无法登录使用Oath-2的应用程序并获得unsupported_grant_type错误。我正在使用Alamofire发布登录数据但无法成功。我在哪做错？我无法解决问题。

func sendFeedback（）

func sendFeedback(){


        let parameters = [

            "UserName": username_textfield.text! as String,
            "Password": password_textfield.text! as String,
            "grant_type": "Password" as String,
                    ]


        Alamofire.upload(multipartFormData: { multipartFormData in

            for (key, value) in parameters {
                multipartFormData.append((value.data(using: .utf8))!, withName: key)
            }}, to: "http://192.168.100.5:84/Token", method: .post, headers: ["Authorization": "auth_token"],
                encodingCompletion: { encodingResult in
                    switch encodingResult {
                    case .success(let upload, _, _):
                        upload.response { [weak self] response in
                            guard self != nil else {
                                return
                            }
                            debugPrint(response)
//                            self?.view.hideToastActivity()
                            self?.view.makeToast(message: "Send Successfull. !!!")

                        }
                        upload.uploadProgress(queue: DispatchQueue(label: "uploadQueue"), closure: { (progress) in


                        })
                    case .failure(let encodingError):
                        print("errorss:\(encodingError)")
                    }
        })

    }

我的状态代码为400.如何解决此问题？