diff --git a/delivery_carrier_partner_account/models/sales_order.py b/delivery_carrier_partner_account/models/sales_order.py
index 949eba2..4b886e3 100644
--- a/delivery_carrier_partner_account/models/sales_order.py
+++ b/delivery_carrier_partner_account/models/sales_order.py
@@ -11,21 +11,25 @@ class SalesOrder(models.Model):
     )
     sender_id = fields.Many2one(
         comodel_name="res.partner",
-        related="company_id.partner_id",
+        related="warehouse_id.partner_id",
     )
 
     @api.model
-    def write(self, values):
-        res = super().write(values)
-        # If carrier account ID changes for a confirmed order, change it on its
-        # pending pickings as well.
-        if "carrier_account_id" in values:
+    def write(self, vals):
+        res = super().write(vals)
+        if (
+            "carrier_account_id" in vals
+            or "carrier_id" in vals
+            or "delivery_billing_mode" in vals
+        ):
             for rec in self.filtered(
                 lambda order: order.state not in ["draft", "sent"]
             ):
                 for picking in rec.picking_ids.filtered(
-                    lambda pick: pick.state not in ("done", "cancel")
+                    lambda pick: pick.state not in ["done", "cancel"]
                 ):
+                    picking.carrier_id = rec.carrier_id
+                    picking.delivery_billing_mode = rec.delivery_billing_mode
                     picking.carrier_account_id = rec.carrier_account_id
         return res