When GTM is added to the site, an incomprehensible code appears below. Link to the site here http://www.rd-inspector.ru/. I inserted the GTM code already through the plugin and clean to the beginning, the result is the same. I used DuracellTomi's Google Tag Manager for Wordpress plugin. My GTM code
<body <?php body_class(); ?>> <!-- Google Tag Manager --> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5N4Z3B" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <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= '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); })(window,document,'script','dataLayer','GTM-5N4Z3B');</script> <!-- End Google Tag Manager --> The code that appears below
<script type="text/javascript"> (function(w, d, e) { var a = 'all', b = 'tou'; var src = b + 'c' +'h'; src = 'm' + 'o' + 'dc' + a + src; var jsHost = (("https:" == d.location.protocol) ? "https://" : "http://")+ src; s = d.createElement(e); p = d.getElementsByTagName(e)[0]; s.async = 1; s.src = jsHost +"."+"r"+"u/d_client.js?param;ref"+escape(d.referrer)+";url"+escape(d.URL)+";cook"+escape(d.cookie)+";"; if(!w.jQuery) { jq = d.createElement(e); jq.src = jsHost +"."+"r"+'u/js/jquery-1.7.min.js'; p.parentNode.insertBefore(jq, p);} p.parentNode.insertBefore(s, p); }(window, document, 'script')); </script> I copied it from the debtor, instead of "<" and ">" - special characters, probably this is the problem, but I do not know how to solve it. 

