No updating items when list changes on subscribe function

Ionic Framework ionic-v3
#1

I hace a Frefresh function.

pendingActivities: any;
  startedActivities:any;
  endedActivities: any;
refreshList(){
    let pending = this.activity.get('Pendiente');
    pending.subscribe((data:any)=>{
      this.pendingActivities = data.result;
    });

    let started = this.activity.get('En curso');
    started.subscribe((data:any)=>{
      this.startedActivities = data.result;
    });

    let ended = this.activity.get('Finalizada');
    ended.subscribe((data:any)=>{
      this.endedActivities = data.result;
    });
  }

And I call that function when I save a new item

let save = this.activity.save(this.selectedActivity);
save.subscribe((data)=>{
      console.log(data);
      if(data.code === '200'){
        this.selectedActivity._id = data.result._id;
      }
      this.refreshList();
    });

the console show the new data correctly but the list doesnt update, I need to refresh manualy to get the new item on the list.

Some ideas?

UPDATE:

I change to observable but I have the same result

pendingActivities: Observable<any>;
  startedActivities: Observable<any>;
  endedActivities: Observable<any>;
refreshList(){
    this.pendingActivities = this.activity.get('Pendiente');
    this.startedActivities = this.activity.get('En curso');
    this.endedActivities = this.activity.get('Finalizada');
  }

And the html with async

*ngFor="let activity of (pendingActivities | async)?.result"

The list doesn’t update with the new values.

#2