Deleted broken schedules still run

[xiaoniu-578fa6bff964d005]

I am using django-q.models.Schedule and find it keep on logging "ERROR Failed ..." even I have deleted all schedule from admin console.

That's how I got this:
I used django-q.tasks.schedule to add some schedules. Later, I found that the number of arguments for the function is wrong, so I delete these schedule in admin console. However django-q kept on retring running this broken task and failed over and over.

Now I have no Schedule object in “/admin/django_q/schedule”, but after I run python manage.py qcluster, I got

23:55:43 [Q] INFO Process-1:2 ready for work at 3022
23:55:43 [Q] INFO Process-1:3 monitoring at 3023
23:55:43 [Q] INFO Process-1:4 pushing tasks at 3024
23:55:43 [Q] INFO Process-1:1 ready for work at 3021
23:55:43 [Q] INFO Process-1 guarding cluster at 3020
23:55:43 [Q] INFO Q Cluster-3018 running.
23:55:43 [Q] INFO Enqueued 96
23:55:43 [Q] INFO Process-1 created a task from schedule [CleanExpireCandidateCronJob]
23:55:43 [Q] INFO Process-1:2 processing [missouri-utah-thirteen-red]
23:55:43 [Q] INFO Process-1:1 processing [quiet-red-cola-fillet]
23:55:43 [Q] INFO Process-1:2 processing [zebra-winner-summer-west]
23:55:43 [Q] INFO Process-1:1 processing [fillet-victor-jig-undress]
23:55:43 [Q] INFO Process-1:2 processing [march-black-tango-lemon]
23:55:43 [Q] ERROR Failed [missouri-utah-thirteen-red] - CleanExpireCandidateCronJob() takes 0 positional arguments but 2 were given
23:55:43 [Q] ERROR Failed [quiet-red-cola-fillet] - CleanExpireCandidateCronJob() takes 0 positional arguments but 2 were given
23:55:43 [Q] ERROR Failed [zebra-winner-summer-west] - CleanExpireCandidateCronJob() takes 0 positional arguments but 2 were given
23:55:43 [Q] ERROR Failed [fillet-victor-jig-undress] - CleanExpireCandidateCronJob() takes 0 positional arguments but 2 were given
23:55:43 [Q] ERROR Failed [march-black-tango-lemon] - CleanExpireCandidateCronJob() takes 0 positional arguments but 3 were given
...

My environment:
django.VERSION: (2, 0, 5, 'final', 0)
django-q==0.9.4

[xiaoniu-578fa6bff964d005]

I found that delete all the items in OrmQ models will remove old broken schedules.