diff --git a/src/vitals/core/database.py b/src/vitals/core/database.py
index b85b3de..11ccad9 100644
--- a/src/vitals/core/database.py
+++ b/src/vitals/core/database.py
@@ -531,13 +531,20 @@ def add_user(user: User) -> int:
         return cursor.lastrowid
 
 
-def _parse_datetime(value) -> datetime:
+def _parse_datetime(value) -> Optional[datetime]:
     """将字符串或 datetime 转换为 datetime 对象"""
     if value is None:
         return None
     if isinstance(value, datetime):
         return value
-    return datetime.fromisoformat(value)
+    # MySQL 可能返回 date 类型
+    if isinstance(value, date):
+        return datetime.combine(value, datetime.min.time())
+    # 尝试解析字符串
+    try:
+        return datetime.fromisoformat(value)
+    except (TypeError, ValueError):
+        return None
 
 
 def _parse_date(value) -> date:
diff --git a/src/vitals/vision/providers/qwen.py b/src/vitals/vision/providers/qwen.py
index c2837b0..1f9aab7 100644
--- a/src/vitals/vision/providers/qwen.py
+++ b/src/vitals/vision/providers/qwen.py
@@ -79,6 +79,12 @@ class QwenVisionAnalyzer:
                 headers=headers,
                 json=payload,
             )
+            # 处理认证错误
+            if response.status_code == 401:
+                raise ValueError(
+                    "API Key 无效或已过期。请检查 DashScope API Key 是否正确配置。"
+                    "可以在管理页面设置 API Key，或通过环境变量 DASHSCOPE_API_KEY 配置。"
+                )
             response.raise_for_status()
             result = response.json()
 
@@ -135,6 +141,12 @@ class QwenVisionAnalyzer:
                 headers=headers,
                 json=payload,
             )
+            # 处理认证错误
+            if response.status_code == 401:
+                raise ValueError(
+                    "API Key 无效或已过期。请检查 DashScope API Key 是否正确配置。"
+                    "可以在管理页面设置 API Key，或通过环境变量 DASHSCOPE_API_KEY 配置。"
+                )
             response.raise_for_status()
             result = response.json()