diff --git a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
index 80be2c8..a68c368 100644
--- a/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
+++ b/erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py
@@ -1058,7 +1058,7 @@
 
 
 @frappe.whitelist()
-def block_invoice(name, hold_comment, release_date):
+def block_invoice(name, release_date, hold_comment=None):
 	if frappe.db.exists('Purchase Invoice', name):
 		pi = frappe.get_doc('Purchase Invoice', name)
 		pi.block_invoice(hold_comment, release_date)