croniter.croniter.CroniterBadCronError: invalid range: range() arg 3 must not be zero

ERPNext Support
1

Hi, I’m seeing this error in the logs.

Traceback (most recent call last):
  File "/home/frappe/frappe-bench/apps/frappe/frappe/utils/scheduler.py", line 67, in enqueue_events_for_site
    enqueue_events(site=site)
  File "/home/frappe/frappe-bench/apps/frappe/frappe/utils/scheduler.py", line 88, in enqueue_events
    frappe.get_doc('Scheduled Job Type', job_type.name).enqueue()
  File "/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/scheduled_job_type/scheduled_job_type.py", line 25, in enqueue
    if self.is_event_due():
  File "/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/scheduled_job_type/scheduled_job_type.py", line 42, in is_event_due
    return self.get_next_execution() <= (current_time or now_datetime())
  File "/home/frappe/frappe-bench/apps/frappe/frappe/core/doctype/scheduled_job_type/scheduled_job_type.py", line 67, in get_next_execution
    get_datetime(self.last_execution or datetime(2000, 1, 1))).get_next(datetime)
  File "/home/frappe/frappe-bench/env/lib/python3.6/site-packages/croniter/croniter.py", line 91, in __init__
    self.expanded, self.nth_weekday_of_month = self.expand(expr_format)
  File "/home/frappe/frappe-bench/env/lib/python3.6/site-packages/croniter/croniter.py", line 523, in expand
    'invalid range: {0}'.format(exc))
croniter.croniter.CroniterBadCronError: invalid range: range() arg 3 must not be zero

Any idea what it is?