diff --git a/src/fastapi_oauth2/middleware.py b/src/fastapi_oauth2/middleware.py
index 6148338..8481947 100644
--- a/src/fastapi_oauth2/middleware.py
+++ b/src/fastapi_oauth2/middleware.py
@@ -109,7 +109,7 @@ async def authenticate(self, request: Request) -> Optional[Tuple[Auth, User]]:
             return Auth(), User()
 
         token_data = Auth.jwt_decode(param)
-        if token_data["exp"] and token_data["exp"] < int(datetime.now(UTC).timestamp()):
+        if token_data["exp"] and token_data["exp"] < int(datetime.now(timezone.utc).timestamp()):
             raise OAuth2AuthenticationError(401, "Token expired")
 
         user = User(token_data)