Five-field cron
Typical order: minute, hour, day-of-month, month, day-of-week (no seconds). Example: `0 9 * * 1-5` weekdays 09:00.
Classic crontab and many schedulers use this shape.
Six-field (with seconds)
Quartz-style adds seconds first: `second minute hour dom month dow`.
Feeding six fields into a five-field validator misaligns fields or fails validation.
Debug habits
Confirm field count + timezone (UTC vs local) from the scheduler docs.
When both day-of-month and day-of-week are set, engines differ on OR vs AND semantics—prefer constraining only one.