UINavigation custom back button image not working in iOS 15 - swift

Question

I want to apply UINavigation custom background image and back button image also for iOS 14 everything is working fine but as I try to run the app on iOS 15 back button image not working instead it's showing the default back button which I want to replace with custom back button image I am using below code
if #available(iOS 15.0, *) {
let appearance = UINavigationBarAppearance()
appearance.configureWithTransparentBackground()
appearance.backgroundImage = image
appearance.setBackIndicatorImage(backButtonImage, transitionMaskImage: backButtonImage)
if Locale.current.languageCode == "fr" {
appearance.titleTextAttributes = [ NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 14), NSAttributedString.Key.foregroundColor: UIColor(hexString: "#231F20")]
} else {
appearance.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor(hexString: "#231F20")]
}
navigationItem.standardAppearance = appearance
navigationItem.scrollEdgeAppearance = appearance
} else {
self.navigationController?.navigationBar.setBackgroundImage(image, for: .default)
self.navigationController?.navigationBar.backIndicatorImage = backButtonImage
self.navigationController?.navigationBar.backIndicatorTransitionMaskImage = backButtonImage
if Locale.current.languageCode == "fr" {
self.navigationController?.navigationBar.titleTextAttributes = [ NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 14), NSAttributedString.Key.foregroundColor: UIColor(hexString: "#231F20")]
} else {
self.navigationController?.navigationBar.titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor(hexString: "#231F20")]
}
}

Answer 1

Sharing with you a common function I have made in a BaseViewController which is the superclass of all my View Controllers.
I Simply call the addBackButton function from viewDidLoad from any of the VC I want to add the back button.
It also handles the back navigation automatically. (takes care if you have presented or pushed a vc)
func addBackButton(tint : UIColor? = nil, backImage : UIImage? = Constants.Images.kImageForBackNavigation){
let buttonForBack = UIButton(type: .custom)
var tintColorForImage = UIColor.white
if tint != nil {
tintColorForImage = tint!
}
let image = backImage!.withRenderingMode(.alwaysTemplate)
buttonForBack.setImage(image, for: .normal)
buttonForBack.imageView?.tintColor = tintColorForImage
buttonForBack.frame = CGRect(x: 0, y: 0, width: 30, height: 30)
buttonForBack.addTarget(self, action: #selector(BaseViewController.closeViewController), for: .touchUpInside)
let barButtonItemForClose = UIBarButtonItem(customView: buttonForBack)
self.navigationItem.setLeftBarButton(barButtonItemForClose, animated: false)
}
#objc func closeViewController(){
if self == self.navigationController?.children.first {
DispatchQueue.main.async {
self.navigationController?.dismiss(animated: true, completion: nil);
}
}
else{
DispatchQueue.main.async {
self.navigationController?.popViewController(animated: true)
}
}
}