update date on page, how to remove on contact

Hello,

i ask once to get the update date on a page and it worked with this php

/**
 * Page date to page 
 */
add_action( 'generate_after_entry_header', 'tu_page_meta' );
function tu_page_meta() {
    if ( is_singular( 'page' ) ) : ?>
        <div class="entry-meta">
            <?php generate_posted_on(); ?>
        </div><!-- .entry-meta -->
    <?php endif;
}

but i would like to remove this update date on contact and about page, how to do that?

Thanks