Google Adwords Conversion Tracking

Google is insisting that my conversion tracking code appear on only one page. I have noticed that on a previous thread (https://kriesi.at/support/topic/google-ads-set-up-conversion-tracking/) that the following code was recommended. However, the moderator added that the code will appear on every page. How can I embed the code on only one page?

function hazlitt_add_goole_scripts(){
if (is_page(9012)) {
?>
<script async src=”https://www.googletagmanager.com/gtag/js?id=AW-123456789″></script>
<script>
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag(‘js’, new Date());

gtag(‘config’, ‘AW-123456789’);
</script>
<script>
gtag(‘event’, ‘conversion’, {‘send_to’: ‘AW-123456789/xxxxxx_NUD’});
</script>
<?php
}
}
add_action(‘wp_head’, ‘hazlitt_add_goole_scripts’);