diff --git a/src/memos/mem_feedback/feedback.py b/src/memos/mem_feedback/feedback.py
index 135058a7d..a57a40676 100644
--- a/src/memos/mem_feedback/feedback.py
+++ b/src/memos/mem_feedback/feedback.py
@@ -2,6 +2,7 @@
 import difflib
 import json
 import re
+import uuid
 
 from datetime import datetime
 from typing import TYPE_CHECKING, Any, Literal
@@ -236,6 +237,7 @@ def _single_add_operation(
         else:
             to_add_memory = new_memory_item.model_copy(deep=True)
 
+        to_add_memory.id = str(uuid.uuid4())
         if to_add_memory.metadata.memory_type == "PreferenceMemory":
             to_add_memory.metadata.preference = new_memory_item.memory
 
@@ -359,9 +361,14 @@ def semantics_feedback(
         lang = detect_lang("".join(memory_item.memory))
         template = FEEDBACK_PROMPT_DICT["compare"][lang]
         if current_memories == []:
-            # retrieve
-            last_user_index = max(i for i, d in enumerate(chat_history_list) if d["role"] == "user")
-            last_qa = " ".join([item["content"] for item in chat_history_list[last_user_index:]])
+            user_indices = [i for i, d in enumerate(chat_history_list) if d["role"] == "user"]
+            if user_indices:
+                last_user_index = max(user_indices)
+                last_qa = " ".join(
+                    [item["content"] for item in chat_history_list[last_user_index:]]
+                )
+            else:
+                last_qa = " ".join([item["content"] for item in chat_history_list])
             supplementary_retrieved = self._retrieve(last_qa, info=info, user_name=user_name)
             feedback_retrieved = self._retrieve(memory_item.memory, info=info, user_name=user_name)