Custom metric installation on Wordpress

Hi all,

I want to create a flow for someone who reaches a URL on my website, I have added this custom code on the page of that URL via Google Tag Manager (GTM), it is not working and unable to see the metric on Klaviyo, any suggestions.

<script type="text/javascript"> 
//Script to initialize Klaviyo object on page load
!function(){if(!window.klaviyo){window._klOnsite=window._klOnsite||[];try{window.klaviyo=new Proxy({},{get:function(n,i){return"push"===i?function(){var n;(n=window._klOnsite).push.apply(n,arguments)}:function(){for(var n=arguments.length,o=new Array(n),w=0;w<n;w++)o[w]=arguments[w];var t="function"==typeof o[o.length-1]?o.pop():void 0,e=new Promise((function(n){window._klOnsite.push([i].concat(o,[function(i){t&&t(i),n(i)}]))}));return e}}})}catch(n){window.klaviyo=window.klaviyo||[],window.klaviyo.push=function(){var n;(n=window._klOnsite).push.apply(n,arguments)}}}}(); </script>
<script type="text/javascript"> 
//Script to track viewed page
klaviyo.track("Viewed Page", {           
      url: window.location.href   
}); 
</script>