title: HttpErrorResponse : ionic 3 & dialogflow
body: <p>I'm using dialog flow in ionic 3.I'm trying to send and get response through http request. This is my home.ts file code.</p>
  
  <pre><code>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 =&gt;{
        console.log(res);
        // let message = new Message(res.result.speech);
        // this.messages.push(message);
        // message_content.value = '';
      }, err =&gt; {
        console.log(err)
      }
      )
    }
  }
  </code></pre>
  
  <p>this is my chatprovider.ts file code</p>
  
  <pre><code>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 =&gt; {
              return res
            })
    }
  
  }
  </code></pre>
  
  <p>This is the error I'm facing </p>
  
  <blockquote>
    <p>polyfills.js:3 POST <a href="https://api.dialogflow.com/v1/query" rel="nofollow noreferrer">https://api.dialogflow.com/v1/query</a> 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.scheduleMacroTask @ polyfills.js:3 (anonymous) @
    polyfills.js:3 o.(anonymous function) @ polyfills.js:2 (anonymous) @
    http.js:2364 Observable._trySubscribe @ Observable.js:172
    Observable.subscribe @ Observable.js:160 subscribeToResult @
    subscribeToResult.js:23 MergeMapSubscriber._innerSub @ mergeMap.js:132
    MergeMapSubscriber._tryNext @ mergeMap.js:129 MergeMapSubscriber._next
    @ mergeMap.js:112 Subscriber.next @ Subscriber.js:93
    ScalarObservable._subscribe @ ScalarObservable.js:49
    Observable._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 (anonymous) @
    HomePage.html:24 handleEvent @ core.js:13589 callWithDebugContext @
    core.js:15098 debugHandleEvent @ core.js:14685 dispatchEvent @
    core.js:10004 (anonymous) @ core.js:10629 (anonymous) @
    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:3 p @ polyfills.js:2 v @ polyfills.js:2
    home.ts:29</p>
  </blockquote>