Ionic 3 with FCM push notifications not working on Android device

Question

Ionic 3 with FCM push notifications not working on Android device

I am trying to send push notifications from PostMan or from a CURL PHP script to my Android device and I am not receiving a message. If I send a notification from the Firebase Console, the notifications will work, I received a push notification. Here is my code on app.component.ts:

import { Component, ViewChild } from '@angular/core';
import { Nav, Platform, AlertController } from 'ionic-angular';
import { HomePage } from '../pages/home/home';
import { StatusBar } from '@ionic-native/status-bar';
import { SplashScreen } from '@ionic-native/splash-screen';
import {FCM, NotificationData} from "@ionic-native/fcm";
@Component({
  templateUrl: 'app.html',
  providers: [Services]
})
export class MyApp {
 @ViewChild(Nav) nav: Nav;
 rootPage:any;
 pages: Array<{title: string, component: any, icono: any}>;

 constructor(public platform: Platform, public alertCtrl: 
 AlertController, public statusBar: StatusBar, public splashScreen: 
 SplashScreen, private fcm: FCM ) {
  this.initializeApp();

  }

 initializeApp() {
 this.platform.ready().then(() => {
  this.statusBar.styleDefault();
  this.splashScreen.hide();

   this.fcm.getToken()
    .then((token:string)=>{
     console.log("The token to use is: ",token);
    })
    .catch(error=>{
      console.error(error);
    });


  this.fcm.onTokenRefresh().subscribe(
    (token:string)=>console.log("Nuevo token",token),
    error=>console.error(error)
  );


  this.fcm.onNotification().subscribe(
    (data:NotificationData)=>{
      if(data.wasTapped){
        console.log("Received in background",JSON.stringify(data));
      }else{

        console.log("Received in foreground",JSON.stringify(data))
      }
     },error=>{
      console.error("Error in notification",error)
     }
  );

});