diff --git a/ext/custom-addons/dp_custom/models/sale.py b/ext/custom-addons/dp_custom/models/sale.py
index 2392c463..5ed7f88d 100644
--- a/ext/custom-addons/dp_custom/models/sale.py
+++ b/ext/custom-addons/dp_custom/models/sale.py
@@ -184,7 +184,7 @@ class SaleOrder(models.Model):
             allowed_update_keys = ['firstname', 'lastname', 'midname', 'email', 'phone']
             for key in list(delivery_vals.keys()):
                 if key not in allowed_update_keys:
-                    del delivery_partner[key]
+                    del delivery_vals[key]
             delivery_partner.write(delivery_vals)
         else:
             if not delivery_vals.get('type', False):