Problem with rxjs

hi guys,
i just upgraded rxjs with below command
npm i rxjs@6 rxjs-compat@6 promise-polyfill --saveyfill --save
after this it showing **

runtime error

**
here is my code

import { Firebase } from '@ionic-native/firebase';
import { Observable } from 'rxjs/Observable';
import { map } from 'rxjs/operators';


geEntityCount() {

    this.storage.get('loginToken').then(value => {
      return new Promise(resolve => {
        this.http.get('api call')
        .pipe(map(res => {
          console.log(res)
        }))
          .subscribe(data => {
            this.entityCount = (data)
          },
            err => {
              alert(err)
            })
      })
    })
  }

errn

please help
Thank You,

okay this is not problem with rxjs. its a problem with firebase