do correct gl entry for debit and credit notes
diff --git a/erpnext/controllers/sales_and_purchase_return.py b/erpnext/controllers/sales_and_purchase_return.py
index 0074560..d609b9e 100644
--- a/erpnext/controllers/sales_and_purchase_return.py
+++ b/erpnext/controllers/sales_and_purchase_return.py
@@ -256,6 +256,9 @@
 			target_doc.dn_detail = source_doc.dn_detail
 			target_doc.expense_account = source_doc.expense_account
 
+	def update_terms(source_doc, target_doc, source_parent):
+		target_doc.payment_amount = -source_doc.payment_amount
+
 	doclist = get_mapped_doc(doctype, source_name,	{
 		doctype: {
 			"doctype": doctype,
@@ -272,6 +275,10 @@
 			},
 			"postprocess": update_item
 		},
+		"Payment Schedule": {
+			"doctype": "Payment Schedule",
+			"postprocess": update_terms
+		}
 	}, target_doc, set_missing_values)
 
 	return doclist