diff --git a/addons/mrp/wizard/mrp_product_produce.py b/addons/mrp/wizard/mrp_product_produce.py
index 6c15772fdab..617e5f012f9 100644
--- a/addons/mrp/wizard/mrp_product_produce.py
+++ b/addons/mrp/wizard/mrp_product_produce.py
@@ -193,9 +193,8 @@ class MrpProductProduceLine(models.TransientModel):
 
     def _check_for_duplicated_serial_numbers(self):
         if self.mapped('lot_id'):
-            lot_names = [ml.lot_id.name for ml in self]
-            recorded_serials_counter = Counter(lot_names)
-            for lot_id, occurrences in recorded_serials_counter.items():
+            lots_map = [(ml.product_id.id, ml.lot_id.name) for ml in self]
+            recorded_serials_counter = Counter(lots_map)
+            for (product_id, lot_id), occurrences in recorded_serials_counter.items():
                 if occurrences > 1 and lot_id is not False:
-                    return _(
-                        'You cannot consume the same serial number twice. Please correct the serial numbers encoded.')
+                    return _('You cannot consume the same serial number twice. Please correct the serial numbers encoded.')
diff --git a/addons/stock/models/stock_move_line.py b/addons/stock/models/stock_move_line.py
index 75a4d960d01..ab164d8a656 100644
--- a/addons/stock/models/stock_move_line.py
+++ b/addons/stock/models/stock_move_line.py
@@ -140,16 +140,17 @@ class StockMoveLine(models.Model):
         :return: an error message directed to the user if needed else False
         """
         if self.mapped('lot_id'):
-            lot_names = [ml.lot_id.name for ml in self]
-            recorded_serials_counter = Counter(lot_names)
-            for lot_id, occurrences in recorded_serials_counter.items():
+            lots_map = [(ml.product_id.id, ml.lot_id.name) for ml in self]
+            recorded_serials_counter = Counter(lots_map)
+            for (product_id, lot_id), occurrences in recorded_serials_counter.items():
                 if occurrences > 1 and lot_id is not False:
-                    return _('You cannot consume the same serial number twice. Please correct the serial numbers encoded.')
+                    return _('You cannot use the same serial number twice. Please correct the serial numbers encoded.')
         elif self.mapped('lot_name'):
-            recorded_serials_counter = Counter(self.mapped('lot_name'))
-            for lot_id, occurrences in recorded_serials_counter.items():
+            lots_map = [(ml.product_id.id, ml.lot_name) for ml in self]
+            recorded_serials_counter = Counter(lots_map)
+            for (product_id, lot_id), occurrences in recorded_serials_counter.items():
                 if occurrences > 1 and lot_id is not False:
-                    return _('You cannot consume the same serial number twice. Please correct the serial numbers encoded.')
+                    return _('You cannot use the same serial number twice. Please correct the serial numbers encoded.')
         return False
 
     @api.model