Why does this happen?
Websites built on WordPress, Drupal, and similar platforms can use cache plugins. A caching plugin creates a static version of your web page that it delivers to visitors. This means visitors will see a cached version when they return to your site to view it again.
When you've made changes, you'll want to empty the cache so it can store the new data or content changes you've made and show those files to your site's visitors.
Caching the tracking script will prevent tracking from being reflected on your site.
Solving the Error
To solve this error, clear your website's cache.
The most common platform where Caching can be an issue is WordPress sites. WordPress sites are typically heavily cached and, therefore, will not update the live public version of your site with changes right away. Therefore, checking the installation right after you've activated the Crazy Egg plugin may result in a false negative.
If you are still having trouble, please Submit a request – Crazy Egg. Please include the name of the Snapshot and the page URL.