reorderArray for Firebase Array in Ionic

Question

I have an app where people track their orders, and each user can create their own statuses that their orders need to be in.

For example, when a user registers, they's make statuses such as "Processing", "Payment Received" and "Shipped" and it is represented in a list.

I am trying to have the ability to reorder these statuses that are stored in a Firebase database.

I have used reorderArray, which works, but then when i go out and back in again, the list is back to what it was previously.

See code below:

order-statuses.ts

this.authUser = this.auth.getLoggedInUser();
    if (this.authUser) {
      this.db.list('/users/' + this.authUser.uid + 
'/OrderStatuses/').subscribe(items => {
        this.orderStatuses = items;
      });
    }   

reorderItems(index){
  this.orderStatuses = reorderArray(this.orderStatuses, index);
}