gtmetrix not fix head code

gtmetrix not fix head code

<!-- Manifest added by SuperPWA - Progressive Web Apps Plugin For WordPress -->
<link rel="manifest" href="/superpwa-manifest.json">
<meta name="theme-color" content="#D5E0EB">
<!— Global site tag (gtag.js) - Google Analytics —>
<script async src="https://www.googletagmanager.com/gtag/js?id=UA-xxxxxxxx-1"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());

  gtag('config', 'UA-xxxxxx-1');

please guide me fix is error