diff --git a/erpnext/hr/doctype/department_approver/department_approver.py b/erpnext/hr/doctype/department_approver/department_approver.py
index b5aa4ac..e65c9f8 100644
--- a/erpnext/hr/doctype/department_approver/department_approver.py
+++ b/erpnext/hr/doctype/department_approver/department_approver.py
@@ -46,7 +46,7 @@
 	elif filters.get("doctype") == "Leave Application":
 		parentfield = "expense_approvers"
 		field_name = "Expense Approver"
-	else:
+	elif filters.get("doctype") == "Shift Request":
 		parentfield = "shift_request_approver"
 		field_name = "Approver"
 	if department_list:
diff --git a/erpnext/hr/doctype/shift_assignment/shift_assignment.py b/erpnext/hr/doctype/shift_assignment/shift_assignment.py
index c81345d..f25d39b 100644
--- a/erpnext/hr/doctype/shift_assignment/shift_assignment.py
+++ b/erpnext/hr/doctype/shift_assignment/shift_assignment.py
@@ -16,7 +16,7 @@
 		self.validate_overlapping_dates()
 
 		if self.end_date and self.end_date <= self.start_date:
-			frappe.throw(_("End Date should not be less than Start Date"))
+			frappe.throw(_("End Date must not be greater than Start Date"))
 
 	def validate_overlapping_dates(self):
 		if not self.name:
@@ -62,7 +62,7 @@
 		if shift_details.docstatus == 0:
 			msg = _("Employee {0} has already applied for {1}: {2}").format(self.employee, self.shift_type, shift_details.name)
 		if shift_details.docstatus == 1 and shift_details.status == "Active":
-			msg = _("Employee {0} already have Active Shift {1}: {2}").format(self.employee, self.shift_type, shift_details.name)
+			msg = _("Employee {0} already has Active Shift {1}: {2}").format(self.employee, self.shift_type, shift_details.name)
 		if shift_details.start_date:
 			msg += _(" from {0}").format(getdate(self.start_date).strftime("%d-%m-%Y"))
 			if shift_details.end_date:
diff --git a/erpnext/hr/doctype/shift_type/shift_type.py b/erpnext/hr/doctype/shift_type/shift_type.py
index 1973564..dfe094e 100644
--- a/erpnext/hr/doctype/shift_type/shift_type.py
+++ b/erpnext/hr/doctype/shift_type/shift_type.py
@@ -79,7 +79,7 @@
 				mark_attendance(employee, date, 'Absent', self.name)
 
 	def get_assigned_employee(self, from_date=None, consider_default_shift=False):
-		filters = {'date':('>=', from_date), 'shift_type': self.name, 'docstatus': '1'}
+		filters = {'start_date':('>=', from_date), 'shift_type': self.name, 'docstatus': '1'}
 		if not from_date:
 			del filters['date']
 		assigned_employees = frappe.get_all('Shift Assignment', 'employee', filters, as_list=True)