diff --git a/addons/stock/models/stock_move_line.py b/addons/stock/models/stock_move_line.py
index 9b07d7e75ef..55e0e88c1b7 100644
--- a/addons/stock/models/stock_move_line.py
+++ b/addons/stock/models/stock_move_line.py
@@ -405,6 +405,8 @@ class StockMoveLine(models.Model):
                         new_reserved_uom_qty = ml.product_id.uom_id._compute_quantity(reserved_qty, ml.product_uom_id, rounding_method='HALF-UP')
                         moves_to_recompute_state |= ml.move_id
                         ml.with_context(bypass_reservation_update=True).reserved_uom_qty = new_reserved_uom_qty
+                        # we don't want to override the new reserved quantity
+                        vals.pop('reserved_uom_qty', None)
 
         # When editing a done move line, the reserved availability of a potential chained move is impacted. Take care of running again `_action_assign` on the concerned moves.
         if updates or 'qty_done' in vals:
diff --git a/addons/stock/tests/test_move.py b/addons/stock/tests/test_move.py
index 43c4e7e670b..be23b6735a3 100644
--- a/addons/stock/tests/test_move.py
+++ b/addons/stock/tests/test_move.py
@@ -3470,6 +3470,32 @@ class StockMove(TransactionCase):
         self.assertEqual(len(self.gather_relevant(self.product_lot, self.stock_location, lot_id=lot1, strict=True)), 0.0)
         self.assertEqual(len(self.gather_relevant(self.product_lot, self.stock_location, lot_id=lot2, strict=True)), 0.0)
 
+    def test_edit_reserved_move_line_9(self):
+        """
+        When writing on the reserved quantity on the SML, a process tries to
+        reserve the quants with that new quantity. If it fails (for instance
+        because the written quantity is more than actually available), this
+        quantity should be reset to 0.
+        """
+        self.env['stock.quant']._update_available_quantity(self.product, self.stock_location, 1.0)
+
+        out_move = self.env['stock.move'].create({
+            'name': self.product.name,
+            'location_id': self.stock_location.id,
+            'location_dest_id': self.customer_location.id,
+            'product_id': self.product.id,
+            'product_uom_qty': 1,
+            'product_uom': self.product.uom_id.id,
+        })
+        out_move._action_confirm()
+        out_move._action_assign()
+
+        # try to manually assign more than available
+        out_move.move_line_ids.reserved_uom_qty = 2
+
+        self.assertTrue(out_move.move_line_ids)
+        self.assertEqual(out_move.move_line_ids.reserved_uom_qty, 0, "The reserved quantity should be cancelled")
+
     def test_edit_done_move_line_1(self):
         """ Test that editing a done stock move line linked to an untracked product correctly and
         directly adapts the transfer. In this case, we edit the sublocation where we take the