Google Tag Manager add by code

Hi,

i want to add Google Tagmanager by code but it doesnt works, here the code:

function google_tag_head_script() {
?>
<script>
(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({‘gtm.start’:
new Date().getTime(),event:’gtm.js’});var f=d.getElementsByTagName(s)[0],
j=d.createElement(s),dl=l!=’dataLayer’?’&l=’+l:”;j.async=true;j.src=
‘https://www.googletagmanager.com/gtm.js?id=’+i+dl;f.parentNode.insertBefore(j,f);
})(window,document,’script’,’dataLayer’,’GTM-0000000′);
</script><?php

}
add_action( ‘wp_head’, ‘google_tag_head_script’ );

function google_tag_after_body_script() {
?>
<!– Google Tag Manager (noscript) –>
<noscript><iframe src=”https://www.googletagmanager.com/ns.html?id=GTM-0000000&#8243;
height=”0″ width=”0″ style=”display:none;visibility:hidden”></iframe></noscript>
<!– End Google Tag Manager (noscript) –><?php

}
add_action(‘wp_footer’, ‘google_tag_after_body_script’);

thanks