diff --git a/addons/sale/models/sale.py b/addons/sale/models/sale.py
index f2627a1520b..574b0318b81 100644
--- a/addons/sale/models/sale.py
+++ b/addons/sale/models/sale.py
@@ -1250,7 +1250,8 @@ class SaleOrderLine(models.Model):
 
         # convert uom and sum all unit_amount of analytic lines to get the delivered qty of SO lines
         # browse so lines and product uoms here to make them share the same prefetch
-        lines_map = {line.id: line for line in self}
+        lines = self.browse([item['so_line'][0] for item in data])
+        lines_map = {line.id: line for line in lines}
         product_uom_ids = [item['product_uom_id'][0] for item in data if item['product_uom_id']]
         product_uom_map = {uom.id: uom for uom in self.env['uom.uom'].browse(product_uom_ids)}
         for item in data: