diff --git a/spring-session-hazelcast/src/integration-test/java/org/springframework/session/hazelcast/FlushImmediateHazelcastIndexedSessionRepositoryITests.java b/spring-session-hazelcast/src/integration-test/java/org/springframework/session/hazelcast/FlushImmediateHazelcastIndexedSessionRepositoryITests.java
new file mode 100644
index 00000000..b316f03c
--- /dev/null
+++ b/spring-session-hazelcast/src/integration-test/java/org/springframework/session/hazelcast/FlushImmediateHazelcastIndexedSessionRepositoryITests.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2014-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.session.hazelcast;
+
+import java.util.Map;
+
+import com.hazelcast.core.HazelcastInstance;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.authority.AuthorityUtils;
+import org.springframework.security.core.context.SecurityContext;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.session.FlushMode;
+import org.springframework.session.hazelcast.config.annotation.web.http.EnableHazelcastHttpSession;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+import org.springframework.test.context.web.WebAppConfiguration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Integration tests for {@link HazelcastIndexedSessionRepository} using embedded
+ * topology, with flush mode set to immediate.
+ *
+ * @author Eleftheria Stein
+ */
+@ExtendWith(SpringExtension.class)
+@ContextConfiguration
+@WebAppConfiguration
+class FlushImmediateHazelcastIndexedSessionRepositoryITests {
+
+	@Autowired
+	private HazelcastIndexedSessionRepository repository;
+
+	@Test
+	void createSessionWithSecurityContextAndFindByPrincipalName() {
+		String username = "saves-" + System.currentTimeMillis();
+
+		HazelcastIndexedSessionRepository.HazelcastSession session = this.repository.createSession();
+		String sessionId = session.getId();
+
+		Authentication authentication = new UsernamePasswordAuthenticationToken(username, "password",
+				AuthorityUtils.createAuthorityList("ROLE_USER"));
+		SecurityContext securityContext = SecurityContextHolder.createEmptyContext();
+		securityContext.setAuthentication(authentication);
+		session.setAttribute("SPRING_SECURITY_CONTEXT", securityContext);
+
+		this.repository.save(session);
+
+		Map<String, HazelcastIndexedSessionRepository.HazelcastSession> findByPrincipalName = this.repository
+				.findByPrincipalName(username);
+
+		assertThat(findByPrincipalName).hasSize(1);
+		assertThat(findByPrincipalName.keySet()).containsOnly(sessionId);
+
+		this.repository.deleteById(sessionId);
+	}
+
+	@EnableHazelcastHttpSession(flushMode = FlushMode.IMMEDIATE)
+	@Configuration
+	static class HazelcastSessionConfig {
+
+		@Bean
+		HazelcastInstance hazelcastInstance() {
+			return HazelcastITestUtils.embeddedHazelcastServer();
+		}
+
+	}
+
+}
diff --git a/spring-session-hazelcast/src/main/java/org/springframework/session/hazelcast/HazelcastIndexedSessionRepository.java b/spring-session-hazelcast/src/main/java/org/springframework/session/hazelcast/HazelcastIndexedSessionRepository.java
index 4de118c6..4f885eec 100644
--- a/spring-session-hazelcast/src/main/java/org/springframework/session/hazelcast/HazelcastIndexedSessionRepository.java
+++ b/spring-session-hazelcast/src/main/java/org/springframework/session/hazelcast/HazelcastIndexedSessionRepository.java
@@ -441,6 +441,7 @@ public class HazelcastIndexedSessionRepository
 						.resolveIndexesFor(this);
 				String principal = (attributeValue != null) ? indexes.get(PRINCIPAL_NAME_INDEX_NAME) : null;
 				this.delegate.setAttribute(PRINCIPAL_NAME_INDEX_NAME, principal);
+				this.delta.put(PRINCIPAL_NAME_INDEX_NAME, principal);
 			}
 			flushImmediateIfNecessary();
 		}