Hi @Thu, thanks, for the followup. I took a look at the domain you listed, and the tracking code appears to be working correctly, but it may be that you are setup with Google Universal analytics, but are using the built in analytics field in site settings, which only supports Google Classic analytics.
To fix this, first remove the code from your site settings:
Next, I would use this code:
<!-- Google Analytics -->
<script>
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-72259746-1', 'auto');
ga('send', 'pageview');
</script>
<!-- End Google Analytics -->
Paste the code above into the Head of your site in site settings, in the custom code tab: Custom code in head and body tags | Webflow University
Save changes and republish your site, and then check again 
I hope this helps!