private void bunifuTileButton_Execute_Click(object sender, EventArgs e)
        {
            if (mode == "view")
            {
                this.Close();
                return;
            }

            ThreadManager.DisplayLoadingScreen();
            VIP newVIP = new VIP();

            try
            {
                Random rnd = new Random();
                newVIP.VipID         = rnd.Next().ToString(); // Dummy init
                newVIP.FullName      = bunifuCustomTextbox_FullName.Text;
                newVIP.DateOfBirth   = Convert.ToDateTime(bunifuCustomTextbox_DoB.Text).Date;
                newVIP.Gender        = bunifuCustomTextbox_Gender.Text;
                newVIP.CivilianID    = bunifuCustomTextbox_CivilianID.Text;
                newVIP.Occupation    = bunifuCustomTextbox_Occupation.Text;
                newVIP.ContactNumber = bunifuCustomTextbox_PhoneNumber.Text;
                newVIP.Address       = bunifuCustomTextbox_Address.Text;
            }
            catch (Exception ex)
            {
                ThreadManager.CloseLoadingScreen();
                ErrorManager.MessageDisplay(ex.Message, "", "Error: Can't get data from fields");
                return;
            }

            string err = "";

            if (mode != "delete")
            {
                err = newVIP.ValidateField();
            }
            if (err != "")
            {
                ThreadManager.CloseLoadingScreen();
                ErrorManager.MessageDisplay(err, "", "Incorrect values");
                return;
            }

            err = manager.AddOrUpdateAVIP(newVIP);
            ThreadManager.CloseLoadingScreen();
            ErrorManager.MessageDisplay(err, "Add/Update a VIP successfully", "Failed to add/update a VIP");

            if (err == "")
            {
                this.Close();
            }
        }