In debug window, both of typescript null check operator "?" and nullish coalescing"??" operator shows systax error Follow

I am using Angular v9, typescript v4 and webstorm 2020.3.

My code:

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  constructor() {
    const data1 = {name: null};
    const data2 = data1.name ?? 'default';
    const data3 = data1?.name ?? 'default'; // ****** break point
  }
}