Double ion-tab-bar issue

I created a blanc app and added a tab bar with 3 routes. The routing and is working win, except i have two similar tab-bars. I did not set it multiple times. The weird thing about it is, that they are contentwise the same (as is created them) but if i for example add a class to the tab-bar it appears just at one of them. Another weird part is, that just the tab-bar ist duplicated and not the whole ion-tabs component.

<ion-app>
  <ion-router-outlet>
    <ion-tabs>
      <ion-tab-bar slot="bottom">
        <ion-tab-button tab="patients">
          <ion-icon name="home"></ion-icon>
        </ion-tab-button>
        <ion-tab-button tab="nurses">
          <ion-icon name="person"></ion-icon>
        </ion-tab-button>
        <ion-tab-button tab="add-care">
          <ion-icon name="add-circle"></ion-icon>
        </ion-tab-button>
      </ion-tab-bar>
    </ion-tabs>
  </ion-router-outlet>
</ion-app>

This is my app.component.html

image