In many cases, this is because the snippet has been added in the wrong place (usually in the header or before the body).

Ensure that the snippet has been placed at the end of the body, just before the closing </body> tag.

As an example:

...
<script>
  var ps_config = {
    workspace_id : "8cd78b29-ae75-4041-a9df-6184a2e8df2"
  };
</script>
<script type="text/javascript" src="https://cdn.loopedin.io/js/widget.min.js?v=0.8" defer="defer"></script>
</body>
</html>