I wanna set special color for title and message of UIAlertController, and refer to the before question , now font-size can be changed but color cannot

below is my extension, it seems background color can work, but i cannot see anything in it.

extension UIAlertController {
    
    func applyTitleMessageStyle() {
        let titleParagraphStyle = NSMutableParagraphStyle()
        titleParagraphStyle.alignment = .center
        let alertController: UIAlertController = self
        if alertController.title != nil {
            let attributedTitle = NSAttributedString(string: alertController.title!, attributes: [
                .foregroundColor: UIColor.red, //William don't work
                //.backgroundColor: UIColor.black, // just a black rectangular
                    .font: UIFont.systemFont(ofSize: 30),
                .paragraphStyle: titleParagraphStyle //William
            ])
            alertController.setValue(attributedTitle, forKey: "attributedTitle")
        }
        if alertController.message != nil {
            let attributedMessage = NSAttributedString(string: alertController.message!, attributes: [
                .foregroundColor: UIColor.red, //William don't work
                //.backgroundColor: UIColor.black, //just a black rectangular
                    .font: UIFont.systemFont(ofSize: 25),
                .paragraphStyle: titleParagraphStyle //William
            ])
            alertController.setValue(attributedMessage, forKey: "attributedMessage")
        }
    }

The screenshot is as follows