diff --git a/erpnext/patches/v4_2/discount_amount.py b/erpnext/patches/v4_2/discount_amount.py
index e23a10e..3ce10ca 100644
--- a/erpnext/patches/v4_2/discount_amount.py
+++ b/erpnext/patches/v4_2/discount_amount.py
@@ -6,7 +6,7 @@
 from frappe.modules import scrub, get_doctype_module
 
 def execute():
-	for dt in ["Quotation", "Sales Order", "Delivery Note", "Sales invoice"]:
+	for dt in ["Quotation", "Sales Order", "Delivery Note", "Sales Invoice"]:
 		frappe.reload_doc(get_doctype_module(dt), "doctype", scrub(dt))
 		frappe.db.sql("""update `tab{0}` set base_discount_amount=discount_amount,
 			discount_amount=discount_amount/conversion_rate""".format(dt))