diff --git a/delivery_purchase/models/purchase_order.py b/delivery_purchase/models/purchase_order.py
index a379615a50..92b66d80d4 100644
--- a/delivery_purchase/models/purchase_order.py
+++ b/delivery_purchase/models/purchase_order.py
@@ -30,7 +30,7 @@ def _compute_delivery_price(self):
             if delivery_lines:
                 item.delivery_price = sum(delivery_lines.mapped("price_unit"))
             else:
-                item.delivery_price = item.carrier_id.purchase_rate_shipment(self)[
+                item.delivery_price = item.carrier_id.purchase_rate_shipment(item)[
                     "price"
                 ]