diff --git a/erpnext/accounts/doctype/pos_invoice/pos_invoice.py b/erpnext/accounts/doctype/pos_invoice/pos_invoice.py
index a5e4d9a..9eded8a 100644
--- a/erpnext/accounts/doctype/pos_invoice/pos_invoice.py
+++ b/erpnext/accounts/doctype/pos_invoice/pos_invoice.py
@@ -743,4 +743,4 @@
 
 
 def on_doctype_update():
-	frappe.db.add_index("POS Invoice", ["customer", "is_return", "return_against"])
+	frappe.db.add_index("POS Invoice", ["return_against"])