diff --git a/src/memos/mem_scheduler/general_scheduler.py b/src/memos/mem_scheduler/general_scheduler.py
index 86718ec82..25d0461c2 100644
--- a/src/memos/mem_scheduler/general_scheduler.py
+++ b/src/memos/mem_scheduler/general_scheduler.py
@@ -168,6 +168,17 @@ def _add_message_consumer(self, messages: list[ScheduleMessageItem]) -> None:
 
                     # Process each message in the batch
                     for msg in batch:
+                        if (
+                            not (msg.user_name or "").strip()
+                            or (msg.user_name or "").strip() == "memosdefault"
+                        ):
+                            logger.warning(
+                                "[AddConsumer] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s content=%s",
+                                msg.user_id,
+                                msg.mem_cube_id,
+                                msg.content,
+                            )
+                            continue
                         prepared_add_items, prepared_update_items_with_original = (
                             self.log_add_messages(msg=msg)
                         )
@@ -212,6 +223,17 @@ def _query_message_consumer(self, messages: list[ScheduleMessageItem]) -> None:
                     continue
                 try:
                     for msg in batch:
+                        if (
+                            not (msg.user_name or "").strip()
+                            or (msg.user_name or "").strip() == "memosdefault"
+                        ):
+                            logger.warning(
+                                "[QueryConsumer] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s content=%s",
+                                msg.user_id,
+                                msg.mem_cube_id,
+                                msg.content,
+                            )
+                            continue
                         event = self.create_event_log(
                             label="addMessage",
                             from_memory_type=USER_INPUT_TYPE,
@@ -257,6 +279,17 @@ def _answer_message_consumer(self, messages: list[ScheduleMessageItem]) -> None:
                     continue
                 try:
                     for msg in batch:
+                        if (
+                            not (msg.user_name or "").strip()
+                            or (msg.user_name or "").strip() == "memosdefault"
+                        ):
+                            logger.warning(
+                                "[AnswerConsumer] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s content=%s",
+                                msg.user_id,
+                                msg.mem_cube_id,
+                                msg.content,
+                            )
+                            continue
                         event = self.create_event_log(
                             label="addMessage",
                             from_memory_type=USER_INPUT_TYPE,
@@ -536,6 +569,17 @@ def _add_message_consumer(self, messages: list[ScheduleMessageItem]) -> None:
 
                     # Process each message in the batch
                     for msg in batch:
+                        if (
+                            not (msg.user_name or "").strip()
+                            or (msg.user_name or "").strip() == "memosdefault"
+                        ):
+                            logger.warning(
+                                "[AddConsumer] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s content=%s",
+                                msg.user_id,
+                                msg.mem_cube_id,
+                                msg.content,
+                            )
+                            continue
                         prepared_add_items, prepared_update_items_with_original = (
                             self.log_add_messages(msg=msg)
                         )
@@ -738,7 +782,15 @@ def process_message(message: ScheduleMessageItem):
                     return
 
                 content = message.content
-                user_name = message.user_name
+                user_name = (message.user_name or "").strip()
+                if not user_name or user_name == "memosdefault":
+                    logger.warning(
+                        "[MemRead] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s mem_ids=%s",
+                        user_id,
+                        mem_cube_id,
+                        content,
+                    )
+                    return
                 info = message.info or {}
 
                 # Parse the memory IDs from content
@@ -1041,7 +1093,15 @@ def process_message(message: ScheduleMessageItem):
                     )
                     return
                 content = message.content
-                user_name = message.user_name
+                user_name = (message.user_name or "").strip()
+                if not user_name or user_name == "memosdefault":
+                    logger.warning(
+                        "[MemReorganize] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s mem_ids=%s",
+                        user_id,
+                        mem_cube_id,
+                        content,
+                    )
+                    return
 
                 # Parse the memory IDs from content
                 mem_ids = json.loads(content) if isinstance(content, str) else content
@@ -1264,6 +1324,15 @@ def _pref_add_message_consumer(self, messages: list[ScheduleMessageItem]) -> Non
 
         def process_message(message: ScheduleMessageItem):
             try:
+                user_name = (message.user_name or "").strip()
+                if not user_name or user_name == "memosdefault":
+                    logger.warning(
+                        "[PrefAdd] Dropping message with empty or default user_name; user_id=%s mem_cube_id=%s content=%s",
+                        message.user_id,
+                        message.mem_cube_id,
+                        message.content,
+                    )
+                    return
                 mem_cube = self.current_mem_cube
                 if mem_cube is None:
                     logger.warning(