diff --git a/src/moldinsight/services/experience_feedback_service.py b/src/moldinsight/services/experience_feedback_service.py
index dbd48c4..c12138c 100644
--- a/src/moldinsight/services/experience_feedback_service.py
+++ b/src/moldinsight/services/experience_feedback_service.py
@@ -223,7 +223,9 @@ class ExperienceFeedbackService:
             role_code = "user"
 
         # 6. 写 ExperienceFeedback
-        now = datetime.now(timezone.utc)
+        # expires_at 列是 naive TIMESTAMP（sa.DateTime()），asyncpg 拒绝 aware datetime
+        # （DataError → 提交反馈 500）；存库/比较统一 naive UTC（同 auth last_login 修复）
+        now = datetime.now(timezone.utc).replace(tzinfo=None)
         new_ttl = now + timedelta(days=FEEDBACK_TTL_DAYS)
         feedback = ExperienceFeedback(
             processing_task_id=processing_task.id,
@@ -274,7 +276,8 @@ class ExperienceFeedbackService:
         排除 expires_at < now() 的过期反馈；按 material_family + is_foam 锚定；
         按 scheme_axis 聚合（adopted/rejected/adjust 计数 + 加权 confidence）。
         """
-        now = datetime.now(timezone.utc)
+        # 同上：expires_at 是 naive TIMESTAMP，SQL 参数也不能传 aware datetime
+        now = datetime.now(timezone.utc).replace(tzinfo=None)
         is_foam_str = "true" if is_foam else "false"
         mat_lower = (material_name or "").lower()
         if "al" in mat_lower and "si" in mat_lower:
diff --git a/src/shared/services/auth_service.py b/src/shared/services/auth_service.py
index f652c30..ed02ae8 100644
--- a/src/shared/services/auth_service.py
+++ b/src/shared/services/auth_service.py
@@ -142,7 +142,11 @@ async def authenticate_user(db_session: AsyncSession, username: str, password: s
     if not verify_password(password, user.hashed_password):
         return None
     
-    user.last_login = datetime.now(timezone.utc)
+    # last_login 列是 TIMESTAMP WITHOUT TIME ZONE（sa.DateTime()），asyncpg 拒绝写入
+    # 带 tzinfo 的 datetime（DataError → 登录 500）：批次5 弃用清理把 utcnow() 换成
+    # aware 时间后，任何一次成功登录都会在 commit 处炸掉。存库统一 naive UTC，
+    # JWT exp（上方 create_access_token）不受影响，仍用 aware。
+    user.last_login = datetime.now(timezone.utc).replace(tzinfo=None)
     await db_session.commit()
     
     return user