iOS15 navigation bar turns black

After upgrading to iOS15, the navigation bar appears black

    if (@available(iOS 15.0, *)) {

           UINavigationBarAppearance *appperance = [[UINavigationBarAppearance alloc]init];

           //add background color

           appperance.backgroundColor = [UIColor whiteColor];

           appperance.shadowImage = [[UIImage alloc]init];

           appperance.shadowColor = nil;

           //Set font color

           [appperance setTitleTextAttributes:@{NSForegroundColorAttributeName:Color_CellTitleColor}];

           self.navigationController.navigationBar.standardAppearance = appperance;

           self.navigationController.navigationBar.scrollEdgeAppearance = appperance;

    }