How to close windows form dynamically

public partial class LinkNotificationMessage : Form
    {
        System.Windows.Forms.Timer timer = new System.Windows.Forms.Timer();
        private readonly VMSCore.ViewModel.LinkNotificationMessage Message;
        public LinkNotificationMessage(VMSCore.ViewModel.LinkNotificationMessage message)
        {
            Message = message;
            InitializeComponent();
            InitiateMessage();

            timer.Tick += new EventHandler(OnTimedEvent);
            timer.Interval = message.TimeToLive;
            timer.Enabled = true;

        }

        private void InitiateMessage()
        {
            lblMessage.Text = Message.Message;
            btnLink.Text = Message.linkText;
            lblMessage.Text = DateTime.Now.Minute.ToString() + " "+  DateTime.Now.Second.ToString();
        }

        private void btnLink_Click(object sender, EventArgs e)
        {
            var processStartInfo = new System.Diagnostics.ProcessStartInfo();
            processStartInfo.UseShellExecute = true;
            processStartInfo.FileName = Message.Link; ;
            System.Diagnostics.Process.Start(processStartInfo);
            Close();
            
        }

        private void OnTimedEvent(object source, EventArgs e)
        {
            this.Close();
            timer.Stop();
        }
    }