Push notifications are not getting received

I followed the documentation of push notification. I set up a firebase, ionic app id and pasted a code from given tutorial.

after that I used to send a testing notification from ionic dashboard. When I sent a notification status is showing ‘sent’ but not any sing notification getting displayed on device.

Please help me to get a notification on android device

import { LocalNotifications } from '@ionic-native/local-notifications';

constructor(public localNotifications: LocalNotifications){}

this.localNotifications.schedule({
            id: 0,
            text: 'Something',
            sound: this.platform.is('android') ? 'file://sound.mp3' : 'file://beep.caf',
          });