# Cancel assignment of existing chained assigned moves
moves_to_unreserve = []
for move in pick.move_lines:
- to_check_moves = [move.move_dest_id]
+ to_check_moves = [move.move_dest_id] if move.move_dest_id.id else []
while to_check_moves:
current_move = to_check_moves.pop()
if current_move.state not in ('done', 'cancel') and current_move.reserved_quant_ids: