diff --git a/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py b/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
index 7077504..6113ee6 100644
--- a/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
+++ b/erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py
@@ -158,8 +158,11 @@
 	def test_purchase_return_for_rejected_qty(self):
 		from erpnext.stock.doctype.warehouse.test_warehouse import get_warehouse
 
-		rejected_warehouse=get_warehouse(company = "_Test Company with perpetual inventory", abbr = " - TCP1", warehouse_name = "_Test Rejected Warehouse").name
-		print(rejected_warehouse)
+		rejected_warehouse="_Test Rejected Warehouse - TCP1"
+		if not frappe.db.exists("Warehouse", rejected_warehouse):
+			get_warehouse(company = "_Test Company with perpetual inventory",
+				abbr = " - TCP1", warehouse_name = "_Test Rejected Warehouse").name
+
 		pr = make_purchase_receipt(company="_Test Company with perpetual inventory", warehouse = "Stores - TCP1", supplier_warehouse = "Work in Progress - TCP1", received_qty=4, qty=2, rejected_warehouse=rejected_warehouse)
 
 		return_pr = make_purchase_receipt(company="_Test Company with perpetual inventory", warehouse = "Stores - TCP1", supplier_warehouse = "Work in Progress - TCP1", is_return=1, return_against=pr.name, received_qty = -4, qty=-2, rejected_warehouse=rejected_warehouse)
@@ -269,20 +272,21 @@
 		if not frappe.db.exists("Item", item_code):
 			item = make_item(item_code, dict(has_serial_no=1))
 
-		serial_no = random_string(5)
+		serial_no = "12903812901"
 		pr_doc = make_purchase_receipt(item_code=item_code,
 			qty=1, serial_no = serial_no)
 
 		self.assertEqual(serial_no, frappe.db.get_value("Serial No",
 			{"purchase_document_type": "Purchase Receipt", "purchase_document_no": pr_doc.name}, "name"))
 
+		#check for the auto created serial nos
 		item_code = "Test Auto Created Serial No"
 		if not frappe.db.exists("Item", item_code):
 			item = make_item(item_code, dict(has_serial_no=1, serial_no_series="KLJL.###"))
 
 		new_pr_doc = make_purchase_receipt(item_code=item_code, qty=1)
 
-		serial_no = get_serial_nos(new_pr_doc[0].serial_no)[0]
+		serial_no = get_serial_nos(new_pr_doc.items[0].serial_no)[0]
 		self.assertEqual(serial_no, frappe.db.get_value("Serial No",
 			{"purchase_document_type": "Purchase Receipt", "purchase_document_no": new_pr_doc.name}, "name"))
 
diff --git a/erpnext/stock/doctype/serial_no/serial_no.py b/erpnext/stock/doctype/serial_no/serial_no.py
index 6ec1645..889f55f 100644
--- a/erpnext/stock/doctype/serial_no/serial_no.py
+++ b/erpnext/stock/doctype/serial_no/serial_no.py
@@ -381,6 +381,7 @@
 			if sr.sales_order and voucher_type == "Stock Entry" \
 				and not args.get('actual_qty', 0) > 0:
 				sr.sales_order = None
+			sr.update_serial_no_reference()
 			sr.save(ignore_permissions=True)
 		elif args.get('actual_qty', 0) > 0:
 			created_numbers.append(make_serial_no(serial_no, args))