django-crontab job not running on developement server

Question

I have the following task in cron.py.

from coreapp.models import Event, User

def update_survey_summary():
    print("starting")
    u = User.objects.get(email="[email protected]")
    e = Event(
      creator=u, 
      title="Some event", 
      location="Some location",
      hosted_by="Admin"
    )
    print("saving...")
    e.save()

And here are crontab config in settings.py:

CRONJOBS = [
    ('*/5 * * * *', 'coreapp.cron.update_survey_summary')
]

INSTALLED_APPS = [
    "django_crontab",
    ...

Basically, the idea is to insert a record every 5 minutes. But nothing happens, and if use python manage.py crontab run <hash>, the job runs successfully and indeed does insert a record in the database. What am I missing?