[fix] [patch]
diff --git a/erpnext/patches/v5_1/rename_roles.py b/erpnext/patches/v5_1/rename_roles.py
index 0ea2e13..452c800 100644
--- a/erpnext/patches/v5_1/rename_roles.py
+++ b/erpnext/patches/v5_1/rename_roles.py
@@ -1,9 +1,9 @@
 import frappe
 
 def execute():
-	frappe.rename_doc("Role", "Material User", "Stock User",
-		merge=frappe.db.exists("Role", "Stock User"))
-	frappe.rename_doc("Role", "Material Manager", "Stock Manager",
-		merge=frappe.db.exists("Role", "Stock User"))
-	frappe.rename_doc("Role", "Material Master Manager", "Item Manager",
-		merge=frappe.db.exists("Role", "Stock User"))
+	if not frappe.db.exists("Role", "Stock User"):
+		frappe.rename_doc("Role", "Material User", "Stock User")
+	if not frappe.db.exists("Role", "Stock Manager"):
+		frappe.rename_doc("Role", "Material Manager", "Stock Manager")
+	if not frappe.db.exists("Role", "Stock Manager"):
+		frappe.rename_doc("Role", "Material Master Manager", "Item Manager")