diff --git a/backend/app/db/models.py b/backend/app/db/models.py
index 2705b5e..39a3323 100644
--- a/backend/app/db/models.py
+++ b/backend/app/db/models.py
@@ -1,14 +1,14 @@
 from sqlalchemy import Boolean, Column, Integer, String, DateTime,ForeignKey,Table
 from sqlalchemy.orm import Mapped,relationship,as_declarative,mapped_column
-from datetime import datetime
+from datetime import datetime,timezone
 from app.db  import Base
 from app.core.security import chacha20Decrypt
 
 @as_declarative()
 class Base:
     id = Column(Integer, primary_key=True, index=True)
-    create_time = Column(DateTime, default=datetime.now)
-    update_time = Column(DateTime, default=datetime.now, onupdate=datetime.now)
+    create_time = Column(DateTime, default=datetime.now(timezone.utc))
+    update_time = Column(DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))
 
 
 userrole = Table(