diff --git a/spark/src/main/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcher.java b/spark/src/main/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcher.java
index 5e80259e09..8feeddcafc 100644
--- a/spark/src/main/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcher.java
+++ b/spark/src/main/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcher.java
@@ -219,9 +219,10 @@ private DispatchQueryResponse handleNonIndexQuery(DispatchQueryRequest dispatchQ
         // get session from request
         SessionId sessionId = new SessionId(dispatchQueryRequest.getSessionId());
         Optional<Session> createdSession = sessionManager.getSession(sessionId);
-        if (createdSession.isPresent()) {
-          session = createdSession.get();
+        if (createdSession.isEmpty()) {
+          throw new IllegalArgumentException("no session found. " + sessionId);
         }
+        session = createdSession.get();
       }
       if (session == null || !session.isReady()) {
         // create session if not exist or session dead/fail
diff --git a/spark/src/main/java/org/opensearch/sql/spark/execution/statement/StatementModel.java b/spark/src/main/java/org/opensearch/sql/spark/execution/statement/StatementModel.java
index adc147c905..2a1043bf73 100644
--- a/spark/src/main/java/org/opensearch/sql/spark/execution/statement/StatementModel.java
+++ b/spark/src/main/java/org/opensearch/sql/spark/execution/statement/StatementModel.java
@@ -36,7 +36,7 @@ public class StatementModel extends StateModel {
   public static final String QUERY_ID = "queryId";
   public static final String SUBMIT_TIME = "submitTime";
   public static final String ERROR = "error";
-  public static final String UNKNOWN = "";
+  public static final String UNKNOWN = "unknown";
   public static final String STATEMENT_DOC_TYPE = "statement";
 
   private final String version;
diff --git a/spark/src/test/java/org/opensearch/sql/spark/asyncquery/AsyncQueryExecutorServiceImplSpecTest.java b/spark/src/test/java/org/opensearch/sql/spark/asyncquery/AsyncQueryExecutorServiceImplSpecTest.java
index cf638effc6..6bc40c009b 100644
--- a/spark/src/test/java/org/opensearch/sql/spark/asyncquery/AsyncQueryExecutorServiceImplSpecTest.java
+++ b/spark/src/test/java/org/opensearch/sql/spark/asyncquery/AsyncQueryExecutorServiceImplSpecTest.java
@@ -45,7 +45,6 @@
 import org.opensearch.common.settings.ClusterSettings;
 import org.opensearch.common.settings.Setting;
 import org.opensearch.common.settings.Settings;
-import org.opensearch.core.common.Strings;
 import org.opensearch.index.query.QueryBuilder;
 import org.opensearch.index.query.QueryBuilders;
 import org.opensearch.plugins.Plugin;
@@ -228,7 +227,6 @@ public void withSessionCreateAsyncQueryThenGetResultThenCancel() {
     // 2. fetch async query result.
     AsyncQueryExecutionResponse asyncQueryResults =
         asyncQueryExecutorService.getAsyncQueryResults(response.getQueryId());
-    assertTrue(Strings.isEmpty(asyncQueryResults.getError()));
     assertEquals(StatementState.WAITING.getState(), asyncQueryResults.getStatus());
 
     // 3. cancel async query.
@@ -462,7 +460,7 @@ public void recreateSessionIfNotReady() {
   }
 
   @Test
-  public void submitQueryInInvalidSessionWillCreateNewSession() {
+  public void submitQueryInInvalidSessionThrowException() {
     LocalEMRSClient emrsClient = new LocalEMRSClient();
     AsyncQueryExecutorService asyncQueryExecutorService =
         createAsyncQueryExecutorService(emrsClient);
@@ -470,14 +468,16 @@ public void submitQueryInInvalidSessionWillCreateNewSession() {
     // enable session
     enableSession(true);
 
-    // 1. create async query with invalid sessionId
-    SessionId invalidSessionId = SessionId.newSessionId(DATASOURCE);
-    CreateAsyncQueryResponse asyncQuery =
-        asyncQueryExecutorService.createAsyncQuery(
-            new CreateAsyncQueryRequest(
-                "select 1", DATASOURCE, LangType.SQL, invalidSessionId.getSessionId()));
-    assertNotNull(asyncQuery.getSessionId());
-    assertNotEquals(invalidSessionId.getSessionId(), asyncQuery.getSessionId());
+    // 1. create async query.
+    SessionId sessionId = SessionId.newSessionId(DATASOURCE);
+    IllegalArgumentException exception =
+        assertThrows(
+            IllegalArgumentException.class,
+            () ->
+                asyncQueryExecutorService.createAsyncQuery(
+                    new CreateAsyncQueryRequest(
+                        "select 1", DATASOURCE, LangType.SQL, sessionId.getSessionId())));
+    assertEquals("no session found. " + sessionId, exception.getMessage());
   }
 
   private DataSourceServiceImpl createDataSourceService() {
diff --git a/spark/src/test/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcherTest.java b/spark/src/test/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcherTest.java
index 95b6033d12..743274d46c 100644
--- a/spark/src/test/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcherTest.java
+++ b/spark/src/test/java/org/opensearch/sql/spark/dispatcher/SparkQueryDispatcherTest.java
@@ -327,6 +327,26 @@ void testDispatchSelectQueryReuseSession() {
     Assertions.assertEquals(MOCK_SESSION_ID, dispatchQueryResponse.getSessionId());
   }
 
+  @Test
+  void testDispatchSelectQueryInvalidSession() {
+    String query = "select * from my_glue.default.http_logs";
+    DispatchQueryRequest queryRequest = dispatchQueryRequestWithSessionId(query, "invalid");
+
+    doReturn(true).when(sessionManager).isEnabled();
+    doReturn(Optional.empty()).when(sessionManager).getSession(any());
+    DataSourceMetadata dataSourceMetadata = constructMyGlueDataSourceMetadata();
+    when(dataSourceService.getRawDataSourceMetadata("my_glue")).thenReturn(dataSourceMetadata);
+    doNothing().when(dataSourceUserAuthorizationHelper).authorizeDataSource(dataSourceMetadata);
+    IllegalArgumentException exception =
+        Assertions.assertThrows(
+            IllegalArgumentException.class, () -> sparkQueryDispatcher.dispatch(queryRequest));
+
+    verifyNoInteractions(emrServerlessClient);
+    verify(sessionManager, never()).createSession(any());
+    Assertions.assertEquals(
+        "no session found. " + new SessionId("invalid"), exception.getMessage());
+  }
+
   @Test
   void testDispatchSelectQueryFailedCreateSession() {
     String query = "select * from my_glue.default.http_logs";