CF7 validation on frontend

add_filter('wpcf7_validate_email*', 'text_confirmation_validation_email', 20, 2);

function text_confirmation_validation_email($result, $tag)
{
    $tag = new WPCF7_Shortcode($tag);
    $wpcf7 = WPCF7_ContactForm::get_current();
    $form_id = $wpcf7->id;
    if ($form_id == '555333' or $form_id == '333555') {
        if ('email-697' == $tag->name) {
            $email = isset($_POST[$tag->name]) ? trim($_POST[$tag->name]) : '';
            $email_arr = array('aol', '@aol', '@smt.com", 'contain_smt' );
            foreach ($email_arr as $value) {
                $pos      = stristr($email, $value);
                if ($pos !== FALSE) {
                    $result->invalidate($tag, "Please enter a valid mail" . $pos);
                }
            }
        }
    }

    return $result;
}