diff --git a/ext/custom-addons/dp_custom/models/sale.py b/ext/custom-addons/dp_custom/models/sale.py
index 7bd3bf93..58e5ffc6 100644
--- a/ext/custom-addons/dp_custom/models/sale.py
+++ b/ext/custom-addons/dp_custom/models/sale.py
@@ -553,7 +553,8 @@ class SaleOrder(models.Model):
         if vals.get('order_line',False):
             self._reset_sequence()
 
-        self.partner_id.last_order_changed = datetime.now()
+        if self.partner_id:
+            self.partner_id.last_order_changed = datetime.now()
 
         return res