diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
index 68da9ea1657c..cb0803db932c 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.py
@@ -2678,6 +2678,10 @@ def postprocess_dunning(source, target):
 				target.closing_text = letter_text.get("closing_text")
 				target.language = letter_text.get("language")
 
+		# update outstanding
+		if source.payment_schedule and len(source.payment_schedule) == 1:
+			target.overdue_payments[0].outstanding = source.get("outstanding_amount")
+
 		target.validate()
 
 	return get_mapped_doc(