How to unregister an event in C++

[hamu777]

I want to register and unregister events in the main window, but I get an access violation exception error when I try to unregister an event. I know how to unregister an event using the token I obtain during registration, but how can I clear all events in C++?

namespace winrt::TestApp::implementation
{
    void MainWindow::InitializeComponent(void)
    {
       MainWindow_ContentT<MainWindow_Content>::InitializeComponent();
       
       // 1. add event
        this->Activated( { this, &MainWindow::OnActivated } );
        
        // 2. event all delete　<<   Error
        this->Activated( nullptr );
    }
  }