Capacitor native plugin

I tried this plugin as tutorial

my test simple page class:

export class Page1Page implements OnInit {

  label1 = 'label1'

  constructor(
    private platform: Platform,
    private extendedDeviceInformation: ExtendedDeviceInformation
  ) {
    console.log('call constructor')
  }

  showInfo() {
    this.label1 = this.extendedDeviceInformation.cpumhz
    const obj = this.extendedDeviceInformation
    console.log('extendedDeviceInformation', obj, obj.cpumhz, obj.memory);
  }

  ngOnInit() {
    console.log('call ngOnInit')

    this.platform.ready().then((result) => {
      console.log('platform ready', result)
      this.showInfo()
    })

  }

  clickButton1() {
    console.log('clickButton1!');
    this.showInfo()
  }

}

In source of this plugin:
https://raw.githubusercontent.com/danielehrhardt/cordova-plugin-extended-device-information/master/www/extended-device-information.js

we can see line:
console.log(‘Device Data’, info);

In my console this displayed as expected (red arrow on my screenshot)
But object this.extendedDeviceInformation in my page class is always empty (green arrows)
I try wrap it to ready, click handler etc.

My question is how to fix this? Thanks!

p.s code of my view template

...
<h1>Label1: {{label1}}</h1>
<ion-button (click)="clickButton1()" expand="block">button1</ion-button>
...

p.p.s I have tried also similar plugins, they work as expected. (Device, AppVersion, BuildInfo, etc)