How to display Last Updated Date at the bottom of the page

Hello, I added this script to display the date of update of my pages, but the date is displayed on top. How to put it at the bottom ?
I use the child theme.

function show_last_updated( $content ) {
  $u_time = get_the_time('U');
  $u_modified_time = get_the_modified_time('U');
  if ($u_modified_time >= $u_time + 86400) {
    $updated_date = get_the_modified_time('j F Y');
    $updated_time = get_the_modified_time('h:i a');
    $custom_content .= '<p class="last-updated-date">Mis à jour le '. $updated_date . '</p>';
  }
  $custom_content .= $content;
  return $custom_content;
}
add_filter( 'the_content', 'show_last_updated' );

Thank you ??