Firebase database

#1

I have been creating a simple ionic app, using firebase as my login and database. i have been following this video https://www.youtube.com/watch?v=uESqBwFVf1Q . Once I get to the end I have no errors happening but my database doesntstore the information the way his does. I think I missed something simple in setting up the database but im not sure what?

HTML file:

<!--
  Generated template for the ProfilePage page.

  See http://ionicframework.com/docs/components/#navigation for more info on
  Ionic pages and navigation.
-->
<ion-header>

  <ion-navbar>
    <ion-title>Profile</ion-title>
  </ion-navbar>

</ion-header>


<ion-content padding>


<ion-item>
<ion-label floating>UserName</ion-label>
<ion-input> [(ngModel)]="profile.username"</ion-input>
</ion-item>


<ion-item>
<ion-label floating>First Name</ion-label>
<ion-input> [(ngModel)]="profile.firstname"</ion-input>
</ion-item>

<ion-item>
<ion-label floating>Last Name</ion-label>
<ion-input> [(ngModel)]="profile.lastname"</ion-input>
</ion-item>

<button ion-button clear block (click)="createProfile()">Create Profile</button>
</ion-content>

TS file:

import { Component } from '@angular/core';
import { IonicPage, NavController, NavParams } from 'ionic-angular';
import { HomePage } from '../home/home';
import { AngularFireAuth } from "angularfire2/auth";
import { AngularFireDatabase } from "angularfire2/database"; 
import { Profile } from '../../models/profile';
/**
 * Generated class for the ProfilePage page.
 *
 * See https://ionicframework.com/docs/components/#navigation for more info on
 * Ionic pages and navigation.
 */

@IonicPage()
@Component({
  selector: 'page-profile',
  templateUrl: 'profile.html',
})
export class ProfilePage {

profile = {} as Profile;
  constructor(private  afAuth: AngularFireAuth, private afDatabase: AngularFireDatabase, public navCtrl: NavController, public navParams: NavParams) {
  }

//check `` and ''
createProfile(){
	this.afAuth.authState.take(1).subscribe(auth=> {
		this.afDatabase.object(`profile/${auth.uid}`).set(this.profile) 
	 	.then(() => this.navCtrl.setRoot(HomePage));
	})
}

  ionViewDidLoad() {
    console.log('ionViewDidLoad ProfilePage');
  }

}

Any ideas what I could do to solve this issue?