diff --git a/lightrag/api/routers/document_routes.py b/lightrag/api/routers/document_routes.py
index c513c7ce..aa5af7e5 100644
--- a/lightrag/api/routers/document_routes.py
+++ b/lightrag/api/routers/document_routes.py
@@ -20,13 +20,14 @@ from lightrag.base import DocProcessingStatus, DocStatus
 from lightrag.api.utils_api import get_combined_auth_dependency
 from ..config import global_args
 
+
 # Function to format datetime to ISO format string with timezone information
 def format_datetime(dt: Any) -> Optional[str]:
     """Format datetime to ISO format string with timezone information
-    
+
     Args:
         dt: Datetime object, string, or None
-        
+
     Returns:
         ISO format string with timezone information, or None if input is None
     """
@@ -34,16 +35,17 @@ def format_datetime(dt: Any) -> Optional[str]:
         return None
     if isinstance(dt, str):
         return dt
-    
+
     # Check if datetime object has timezone information
     if isinstance(dt, datetime):
         # If datetime object has no timezone info (naive datetime), add UTC timezone
         if dt.tzinfo is None:
             dt = dt.replace(tzinfo=timezone.utc)
-    
+
     # Return ISO format string with timezone information
     return dt.isoformat()
 
+
 router = APIRouter(
     prefix="/documents",
     tags=["documents"],
@@ -338,7 +340,7 @@ class PipelineStatusResponse(BaseModel):
     history_messages: Optional[List[str]] = None
     update_status: Optional[dict] = None
 
-    @field_validator('job_start', mode='before')
+    @field_validator("job_start", mode="before")
     @classmethod
     def parse_job_start(cls, value):
         """Process datetime and return as ISO format string with timezone"""
@@ -1263,12 +1265,8 @@ def create_document_routes(
                             content_summary=doc_status.content_summary,
                             content_length=doc_status.content_length,
                             status=doc_status.status,
-                            created_at=format_datetime(
-                                doc_status.created_at
-                            ),
-                            updated_at=format_datetime(
-                                doc_status.updated_at
-                            ),
+                            created_at=format_datetime(doc_status.created_at),
+                            updated_at=format_datetime(doc_status.updated_at),
                             chunks_count=doc_status.chunks_count,
                             error=doc_status.error,
                             metadata=doc_status.metadata,
diff --git a/lightrag/kg/postgres_impl.py b/lightrag/kg/postgres_impl.py
index 578140ff..75de70f2 100644
--- a/lightrag/kg/postgres_impl.py
+++ b/lightrag/kg/postgres_impl.py
@@ -1028,7 +1028,7 @@ class PGDocStatusStorage(DocStatusStorage):
             # Remove timezone information, store utc time in db
             created_at = parse_datetime(v.get("created_at"))
             updated_at = parse_datetime(v.get("updated_at"))
-            
+
             # chunks_count is optional
             await self.db.execute(
                 sql,
diff --git a/lightrag/lightrag.py b/lightrag/lightrag.py
index 8891bc2a..c16a7b68 100644
--- a/lightrag/lightrag.py
+++ b/lightrag/lightrag.py
@@ -958,7 +958,9 @@ class LightRAG:
                                             "content_summary": status_doc.content_summary,
                                             "content_length": status_doc.content_length,
                                             "created_at": status_doc.created_at,
-                                            "updated_at": datetime.now(timezone.utc).isoformat(),
+                                            "updated_at": datetime.now(
+                                                timezone.utc
+                                            ).isoformat(),
                                             "file_path": file_path,
                                         }
                                     }
@@ -1018,7 +1020,9 @@ class LightRAG:
                                         "content_summary": status_doc.content_summary,
                                         "content_length": status_doc.content_length,
                                         "created_at": status_doc.created_at,
-                                        "updated_at": datetime.now(timezone.utc).isoformat(),
+                                        "updated_at": datetime.now(
+                                            timezone.utc
+                                        ).isoformat(),
                                         "file_path": file_path,
                                     }
                                 }
@@ -1053,7 +1057,9 @@ class LightRAG:
                                         "content_summary": status_doc.content_summary,
                                         "content_length": status_doc.content_length,
                                         "created_at": status_doc.created_at,
-                                        "updated_at": datetime.now(timezone.utc).isoformat(),
+                                        "updated_at": datetime.now(
+                                            timezone.utc
+                                        ).isoformat(),
                                         "file_path": file_path,
                                     }
                                 }
diff --git a/lightrag_webui/src/components/documents/PipelineStatusDialog.tsx b/lightrag_webui/src/components/documents/PipelineStatusDialog.tsx
index 8ca76d01..2a2c5d93 100644
--- a/lightrag_webui/src/components/documents/PipelineStatusDialog.tsx
+++ b/lightrag_webui/src/components/documents/PipelineStatusDialog.tsx
@@ -158,7 +158,7 @@ export default function PipelineStatusDialog({
           <div className="rounded-md border p-3 space-y-2">
             <div>{t('documentPanel.pipelineStatus.jobName')}: {status?.job_name || '-'}</div>
             <div className="flex justify-between">
-              <span>{t('documentPanel.pipelineStatus.startTime')}: {status?.job_start 
+              <span>{t('documentPanel.pipelineStatus.startTime')}: {status?.job_start
                 ? new Date(status.job_start).toLocaleString(undefined, {
                   year: 'numeric',
                   month: 'numeric',
@@ -166,7 +166,7 @@ export default function PipelineStatusDialog({
                   hour: 'numeric',
                   minute: 'numeric',
                   second: 'numeric'
-                }) 
+                })
                 : '-'}</span>
               <span>{t('documentPanel.pipelineStatus.progress')}: {status ? `${status.cur_batch}/${status.batchs} ${t('documentPanel.pipelineStatus.unit')}` : '-'}</span>
             </div>