Visual Studio Code – Removing item from ListBox – unhandled exception in WPF?

I have this code in my MainWindow.
The user enters Name, Phone and Email in the fields provided, selects Location and then the Name appears in the listbox, lstClients.

I’m trying to write a method to remove a selected name from the listbox.

namespace WpfApp_Employment_Help
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        // client list

        List<Client> ClientList = new List<Client>();
        public MainWindow()
        {
            InitializeComponent();
        }

        // method to select location via radio button
        public string GetSelectedLocation()
        {
            string selected = string.Empty;
           if (RBLocE.IsChecked == true) { selected = "Edinburgh"; }
           else if (RBLocG.IsChecked == true) { selected = "Glasgow"; }
           else if (RBLocO.IsChecked == true) { selected = "Other"; }
           
           return selected;
        }


        // method to create a new client on click
        private void newClient(object sender, RoutedEventArgs e)
        {
            Client c = new Client(boxClientName.Text, boxClientPhone.Text, boxClientEmail.Text, GetSelectedLocation());
            boxClientName.Clear();
            boxClientPhone.Clear();
            boxClientEmail.Clear();
            ClientList.Add(c);
            lstClients.ItemsSource = null;
            lstClients.ItemsSource = ClientList;
        }

        // method to id selected client
        private void AssignID(object sender, RoutedEventArgs e)
        {
            Client c = lstClients.SelectedItem as Client;
            if (c != null)
            {
                c.AssignID();
            }
            lstClients.ItemsSource = null;
            lstClients.ItemsSource = ClientList;
        }

        //    method to remove selected client

        private void RemoveClient(object sender, RoutedEventArgs e)
        {
            lstClients.Items.Remove(lstClients.SelectedItem);
        }

             
        
    }
}

When I run this code, I get Unhandled Exception:
System.InvalidOperationException: ‘Operation is not valid while ItemsSource is in use. Access and modify elements with ItemsControl.ItemsSource instead.’

how can I rewrite my RemoveClient method?
my code for the Client class is this:

   public partial class Client
     {
        public string Name { get; set; }
        public string Phone { get; set; }
        public string Email { get; set; }

        public string Location { get; }

        public bool IDed { get; private set; }

        public Client(string n, string p, string e, string l)
        {
            Name = n;
            Phone = p;
            Email = e;
            Location = l;

        }
    }

I have Visual Studio 2022 which has been recently updated.

I have also tried the following solution but it gives me another unhandled error?
It looks like I need to change List </string/> and string to something else. but what?

        private void RemoveClient(object sender, EventArgs e)
        {
            if (lstClients.Items.Count >= 1)
            {
                if (lstClients.SelectedValue != null)
                {
                    var items = (List<string>)lstClients.ItemsSource;

                    var item = (string)lstClients.SelectedValue;
                    lstClients.ItemsSource = null;
                    lstClients.Items.Clear();
                    items.Remove(item);
                    lstClients.ItemsSource = items;
                }
            }
            else
            {
                System.Windows.Forms.MessageBox.Show("No ITEMS Found");
            }
        }

System.InvalidCastException: 'Unable to cast object of type 'System.Collections.Generic.List`1[WpfApp_Employment_Help.Client]' to type 'System.Collections.Generic.List`1[System.String]'.'