Please help me insert this code in a wordpress php theme file.

On my previous theme that I was customizing, I wanted to insert an ad banner into a wordpress theme home page footer. Below is the original code at the end of the home page php template.

</article>
<?php
        if ($i  % 3 == 2) { echo '</div>'; }
        $i++;
        endwhile;
        if ($cb_closer == true) {echo '</div>';}
        cb_page_navi();
        endif;
?>

I figured out I can achieve this by inserting my ad like below. I did that and it worked like a charm.

?> insert ad code here <?php cb_page_navi();

Now I need to achieve same for a new theme that has following home page php code at the bottom. I tried above method but it did not work.

</article>

<?php
        $cb_count++;
        endwhile;
        cb_page_navi( $cb_qry );
        endif;
?>

Can someone please help how to ad my banner code on footer above pagination?