diff --git a/pams/order_book.py b/pams/order_book.py
index b9165ef..341ab56 100644
--- a/pams/order_book.py
+++ b/pams/order_book.py
@@ -143,7 +143,7 @@ def _check_expired_orders(self) -> List[ExpirationLog]:
         for delete_order in delete_orders:
             log: ExpirationLog = ExpirationLog(
                 order_id=delete_order.order_id,
-                market_id=delete_order.order_id,
+                market_id=delete_order.market_id,
                 time=self.time,
                 order_time=delete_order.placed_at,
                 agent_id=delete_order.agent_id,