diff --git a/erpnext/regional/india/utils.py b/erpnext/regional/india/utils.py
index 631fc25..fb421fb 100644
--- a/erpnext/regional/india/utils.py
+++ b/erpnext/regional/india/utils.py
@@ -67,9 +67,9 @@
 	address_name = doc.shipping_address_name or doc.customer_address
 	if address_name:
 		address = frappe.db.get_value("Address", address_name, ["gst_state", "gst_state_number"], as_dict=1)
-		doc.place_of_supply = cstr(address.gst_state_number) + "-" + address.gst_state
+		doc.place_of_supply = cstr(address.gst_state_number) + "-" + cstr(address.gst_state)
 
 # don't remove this function it is used in tests
 def test_method():
 	'''test function'''
-	return 'overridden'
\ No newline at end of file
+	return 'overridden'