Flowable timer event listener is not triggered automatically

we have 2 stages .in the first stage there is only a timer event listener which on completion of 2 min should make the frst stage complete and move to second stage(which was available earlier and now should be active) .the model is working fine when modeling in flowable modeler.but i have created a rest api to get all case instances .even after time elapsed ,the timer event is still available and first stage is still active which means its not even triggering the timer event listener