how to update controller after RSVP.allSettled

After all rsvp promises are done in ember controller, how can I save all error status in controller and update DOM? I got undefined 'this', controller no longer accessible.

export default class someController extends Controller {
  @tracked errorlist = [];

  @action someAction {
    RSVP.allSettled(prommises).then(function(retarray){
      retarray.forEach((retstate) => {
        if (retstate.state == 'rejected') {
          this.errorlist.push(stateRet.reason);   
          //'this' undefined, how to update errlist?
        }
      });
    })
  }
}