private void ChangeBtn_Click(object sender, EventArgs e)
{
TeacherAccount staff = new TeacherAccount();
string staffName = listOfStaff.GetItemText(listOfStaff.SelectedItem);
string email = EmailTbx.Text;
string phone = PhoneTbx.Text;
string status = StatusList.GetItemText(StatusList.SelectedItem);
string text = staff.changePermission(staffName, status, email, phone);
}
