diff --git a/purchase_delivery_split_date/models/purchase.py b/purchase_delivery_split_date/models/purchase.py
index cd66fb581e9..2069746f861 100644
--- a/purchase_delivery_split_date/models/purchase.py
+++ b/purchase_delivery_split_date/models/purchase.py
@@ -132,7 +132,7 @@ def _check_split_pickings(self):
                             continue
                         if (
                             move.picking_id.scheduled_date.date() != date_key
-                            or pickings_by_date[date_key] != move.picking_id
+                            or pickings_by_date.get(date_key, []) != move.picking_id
                         ):
                             if date_key not in pickings_by_date:
                                 copy_vals = line._first_picking_copy_vals(key, line)