Emberjs not sending data on submit

When I'm submitting the form, I get the following response:

{"data":{"attributes":{"title":null,"description":null},"type":"cards"}}

I'm not sure why I am getting title and description as null.

routes/cards/new.js:

actions: {
  save() {
    const newCard = this.get('store').createRecord('card', this.get('model'));
    newCard.save().then((card) => {
      this.transitionTo('cards.all');
    });
  },
  cancel() {
    this.transitionTo('cards');
  }
}

templates/cards/new.hbs:

<form>
  <div>
    <label>Title:</label>
    
  </div>
  <div>
    <label>Body:</label>
    
  </div>
  <div>
    <button >Speichern</button>
    <button >Abbrechen</button>
  </div>
</form>

Repo link: http://ift.tt/1Xv7Dye