How to remove the view?

I am using this code to create and delete a view. All conditions are completed, but the view is not deleted. How to fix it?

@objc func action(sender: UIButton) {
        let a = UIView()
        a.backgroundColor = .green
        
        if settingsButtonState == true {
            settingsButtonState = false
            a.removeFromSuperview()
            print("delete") // this condition is completing but not remove view
        } else {
            settingsButtonState = true
            view.frame = UIScreen.main.bounds
            view.addSubview(a)
            print("add")
        }
    }

You are creating a new UIView every time action is called, so when the settingsButtonState is true, a has no super view to be removed from. You need to store a reference to a and then remove that from the superview.

// Store the view as a property
private let a: UIView?

@objc func action(sender: UIButton) {
    if a == nil {
      a = UIView()
    }
    a.backgroundColor = .green

    if settingsButtonState == true {
      settingsButtonState = false
      a.removeFromSuperview()
    } else {
      settingsButtonState = true
      view.frame = UIScreen.main.bounds
      view.addSubview(a)
    }
}