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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-PPPNBGN');</script>
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I added the optinmonster code already. 

I am marking this as done since I checked and verified GTM on https://www.parakhplasticsurgery.com to be  GTM-PPPNBGN which is the one you have here.