fix:better error message when sales person is none
diff --git a/erpnext/maintenance/doctype/maintenance_schedule/maintenance_schedule.py b/erpnext/maintenance/doctype/maintenance_schedule/maintenance_schedule.py
index 3a64e1a..1ad7fc8 100644
--- a/erpnext/maintenance/doctype/maintenance_schedule/maintenance_schedule.py
+++ b/erpnext/maintenance/doctype/maintenance_schedule/maintenance_schedule.py
@@ -150,7 +150,7 @@
 			elif not d.no_of_visits:
 				throw(_("Please mention no of visits required"))
 			elif not d.sales_person:
-				throw(_("Please select Incharge Person's name"))
+				throw(_("Please select Incharge Person's name for item: {0}".format(d.item_name)))
 
 			if getdate(d.start_date) >= getdate(d.end_date):
 				throw(_("Start date should be less than end date for Item {0}").format(d.item_code))