If you receive the error "days must be smaller than the duration" when duplicating a survey, it's usually caused by a mismatch between the survey's reminder schedule and its duration.
This can happen if the survey duration was changed after reminder notifications were already configured.
To duplicate the survey successfully:
1. Reactivate the survey for one day.
2. Open the survey and edit its launch plan.
3. Remove all configured reminder notifications.
4. Save your changes.
5. Try duplicating the survey again.
Once the survey has been duplicated successfully, you can manually close the original survey by setting its end date to a date in the past.
This workaround resolves conflicts between reminder settings and survey duration that can prevent survey duplication.