private void ClearFormData()
 {
     FirstNameTextBox.Clear();
     LastNameTextBox.Clear();
     EmailAdrTextBox.Clear();
     ContactNumberTextBox.Clear();
 }
        private void ResetForm()
        {
            FirstNameTextBox.Clear();
            LastNameTextBox.Clear();
            EmailAddressTextBox.Clear();
            ContactNumberTextBox.Clear();

            // clear Contact ComboBox List Items
            ContactComboBox.Items.Clear();
        }