Angular HttpErrorResponse:ionic 3&；对话流

我在ionic 3中使用对话流。我试图通过http请求发送和获取响应。这是我的home.ts文件代码

import { Component } from '@angular/core';
import { NavController } from 'ionic-angular';
import { Message } from '../module/message.module';
import { ChatProvider } from '../../providers/chat/chat';
@Component({
  selector: 'page-home',
  templateUrl: 'home.html'
})
export class HomePage {

  messages: Message[] = [];

  constructor(public navCtrl: NavController,private chatprovider: ChatProvider) {

  }

  // ionViewDidLoad(){
  //   let message = new Message("hi")
  //   this.messages.push(message);
  // }

  sendMesage(message_content) {
    this.chatprovider.sendMessage(message_content.value).subscribe(res =>{
      console.log(res);
      // let message = new Message(res.result.speech);
      // this.messages.push(message);
      // message_content.value = '';
    }, err => {
      console.log(err)
    }
    )
  }
}

这是我的chatprovider.ts文件代码

import { HttpClient, HttpHeaders } from '@angular/common/http';
import { Injectable } from '@angular/core';
import 'rxjs/add/operator/map';

@Injectable()
export class ChatProvider {

  url = 'https://api.dialogflow.com/v1/query';
  accessToken = 'xxxxxxxxxxxxxxxxxxxxxxxx';

  constructor(public http: HttpClient) {
    console.log('Hello ChatProvider Provider');
  }

  sendMessage(message: string) {
    let data = {
      lang: "en",
      query: message
    }
    let headers = new HttpHeaders();
    headers.append("Authorization","Bearer" + this.accessToken);
    return this.http.post(this.url, data,{headers: headers})
          .map(res => {
            return res
          })
  }

}

这就是我面临的错误

js:3 POST 403（）s@ polyfills.js:3 t.scheduleTask@polyfills.js:3 onScheduleTask@ polyfills.js:3 t.scheduleTask@polyfills.js:3 r.scheduleTask@ polyfills.js:3 r.scheduleMocrotask@polyfills.js:3（匿名）@ polyfills.js:3 o.（匿名函数）@polyfills.js:2（匿名）@ http.js:2364 Observable.\u trySubscribe@Observable.js:172 Observable.subscribe@Observable.js:160 subscribbetoresult@ subscribeToResult.js:23 MergeMapSubscriber.\u innerSub@mergeMap.js:132 MergeMapSubscriber.\u tryNext@mergeMap.js:129 MergeMapSubscriber.\u下一步 @mergeMap.js:112 Subscriber.next@Subscriber.js:93 ScalarObservable.\u subscribe@ScalarObservable.js:49 可观察的。_trySubscribe@Observable.js:172 Observable.subscribe@ Observable.js:160 MergeMapOperator.call@mergeMap.js:87 Observable.subscribe@Observable.js:157 FilterOperator.call@ filter.js:60 Observable.subscribe@Observable.js:157 MapOperator.call @map.js:56 Observable.subscribe@Observable.js:157 MapOperator.call @map.js:56 Observable.subscribe@Observable.js:157 webpackJsonp.197.HomePage.sendMesage@home.ts:23（匿名）@ HomePage.html:24 handleEvent@core.js:13589 callWithDebugContext@ core.js:15098 debugHandleEvent@core.js:14685 dispatchEvent@ core.js:10004（匿名）@core.js:10629（匿名）@ platform browser.js:2628 t.invokeTask@polyfills.js:3 onInvokeTask@ core.js:4751 t.invokeTask@polyfills.js:3 r.runTask@polyfills.js:3 e、 invokeTask@polyfills.js:3p@polyfills.js:2v@polyfills.js:2 首页。ts:29

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