diff --git a/docs/docs/integrations/memory/mongodb_chat_message_history.ipynb b/docs/docs/integrations/memory/mongodb_chat_message_history.ipynb
index 88771c7680f..7d25eafb38b 100644
--- a/docs/docs/integrations/memory/mongodb_chat_message_history.ipynb
+++ b/docs/docs/integrations/memory/mongodb_chat_message_history.ipynb
@@ -180,7 +180,7 @@
     "chain_with_history = RunnableWithMessageHistory(\n",
     "    chain,\n",
     "    lambda session_id: MongoDBChatMessageHistory(\n",
-    "        session_id=\"test_session\",\n",
+    "        session_id=session_id,\n",
     "        connection_string=\"mongodb://mongo_user:password123@mongo:27017\",\n",
     "        database_name=\"my_db\",\n",
     "        collection_name=\"chat_histories\",\n",