diff --git a/bigtop-manager-ai/bigtop-manager-ai-assistant/src/main/java/org/apache/bigtop/manager/ai/assistant/store/PersistentChatMemoryStore.java b/bigtop-manager-ai/bigtop-manager-ai-assistant/src/main/java/org/apache/bigtop/manager/ai/assistant/store/PersistentChatMemoryStore.java
index d5895ea5..91352880 100644
--- a/bigtop-manager-ai/bigtop-manager-ai-assistant/src/main/java/org/apache/bigtop/manager/ai/assistant/store/PersistentChatMemoryStore.java
+++ b/bigtop-manager-ai/bigtop-manager-ai-assistant/src/main/java/org/apache/bigtop/manager/ai/assistant/store/PersistentChatMemoryStore.java
@@ -32,6 +32,7 @@
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 public class PersistentChatMemoryStore implements ChatMemoryStore {
@@ -80,7 +81,10 @@ public List<ChatMessage> getMessages(Object threadId) {
         if (chatMessages.isEmpty()) {
             return new ArrayList<>();
         } else {
-            return chatMessages.stream().map(this::convertToChatMessage).collect(Collectors.toList());
+            return chatMessages.stream()
+                    .map(this::convertToChatMessage)
+                    .filter(Objects::nonNull)
+                    .collect(Collectors.toList());
         }
     }
 
diff --git a/bigtop-manager-dao/src/main/resources/mapper/postgresql/ChatThreadMapper.xml b/bigtop-manager-dao/src/main/resources/mapper/postgresql/ChatThreadMapper.xml
index fe14e7c5..a742bed3 100644
--- a/bigtop-manager-dao/src/main/resources/mapper/postgresql/ChatThreadMapper.xml
+++ b/bigtop-manager-dao/src/main/resources/mapper/postgresql/ChatThreadMapper.xml
@@ -48,18 +48,13 @@
 
     <insert id="saveWithThreadInfo" parameterType="org.apache.bigtop.manager.dao.po.ChatThreadPO" useGeneratedKeys="true" keyProperty="id">
         INSERT INTO llm_chat_thread (platform_id, user_id, model, thread_info)
-        VALUES (#{platformId}, #{userId}, #{model}, #{threadInfo, typeHandler=org.apache.bigtop.manager.dao.handler.JsonTypeHandler})
-            ON DUPLICATE KEY UPDATE
-            platform_id = VALUES(platform_id),
-            user_id = VALUES(user_id),
-            model = VALUES(model),
-            thread_info = VALUES(thread_info)
+        VALUES (#{platformId}, #{userId}, #{model}, #{threadInfo, typeHandler=org.apache.bigtop.manager.dao.handler.JsonTypeHandler}::json)
     </insert>
 
     <select id="findAllByPlatformId" resultType="org.apache.bigtop.manager.dao.po.ChatThreadPO">
         SELECT *
         FROM llm_chat_thread
-        WHERE platform_id = #{platformId} AND is_deleted = 0
+        WHERE platform_id = #{platformId} AND is_deleted = false
     </select>
 
 </mapper>
\ No newline at end of file
diff --git a/bigtop-manager-dao/src/main/resources/mapper/postgresql/PlatformAuthorizedMapper.xml b/bigtop-manager-dao/src/main/resources/mapper/postgresql/PlatformAuthorizedMapper.xml
index 63e841a3..518d295d 100644
--- a/bigtop-manager-dao/src/main/resources/mapper/postgresql/PlatformAuthorizedMapper.xml
+++ b/bigtop-manager-dao/src/main/resources/mapper/postgresql/PlatformAuthorizedMapper.xml
@@ -40,10 +40,7 @@
 
     <insert id="saveWithCredentials" parameterType="org.apache.bigtop.manager.dao.po.PlatformAuthorizedPO" useGeneratedKeys="true" keyProperty="id">
         INSERT INTO llm_platform_authorized (platform_id, credentials)
-        VALUES (#{platformId}, #{credentials, typeHandler=org.apache.bigtop.manager.dao.handler.JsonTypeHandler})
-            ON DUPLICATE KEY UPDATE
-            platform_id = VALUES(platform_id),
-            credentials = VALUES(credentials)
+        VALUES (#{platformId}, #{credentials, typeHandler=org.apache.bigtop.manager.dao.handler.JsonTypeHandler}::json)
     </insert>
 
 </mapper>
\ No newline at end of file
diff --git a/bigtop-manager-server/src/main/java/org/apache/bigtop/manager/server/service/impl/ChatbotServiceImpl.java b/bigtop-manager-server/src/main/java/org/apache/bigtop/manager/server/service/impl/ChatbotServiceImpl.java
index da363aee..7148ee32 100644
--- a/bigtop-manager-server/src/main/java/org/apache/bigtop/manager/server/service/impl/ChatbotServiceImpl.java
+++ b/bigtop-manager-server/src/main/java/org/apache/bigtop/manager/server/service/impl/ChatbotServiceImpl.java
@@ -217,6 +217,11 @@ public boolean deleteAuthorizedPlatform(Long platformId) {
                 List<ChatThreadPO> chatThreadPOS = chatThreadDao.findAllByPlatformId(authorizedPlatformPO.getId());
                 chatThreadPOS.forEach(chatThread -> chatThread.setIsDeleted(true));
                 chatThreadDao.partialUpdateByIds(chatThreadPOS);
+                for (ChatThreadPO chatThreadPO : chatThreadPOS) {
+                    List<ChatMessagePO> chatMessagePOS = chatMessageDao.findAllByThreadId(chatThreadPO.getId());
+                    chatMessagePOS.forEach(chatMessage -> chatMessage.setIsDeleted(true));
+                    chatMessageDao.partialUpdateByIds(chatMessagePOS);
+                }
                 return true;
             }
         }