You’ve installed the Google Optimize tool with your correct container ID.
But are you getting an error from the Google Optimize Chrome Plugin when you’re trying to preview the variant?
If you receive the following error:
The Google Optimize snippet for the container with ID GTM-******* is not correctly installed on this page. To preview variants for this experiment, make sure the Google Optimize snippet is installed on any pages you want to test.
This page does not have an Optimize snippet for this container. To preview this page and start an experiment, please check that your page has the snippet properly set up.
Make sure you’re logged out of WordPress because MonsterInsights doesn’t load for logged-in users such as Administrators and Editors by default.
That’s it! Now you know what the cause of that error was. Interested in increasing your conversions on your signup forms? See our guide: How to A/B Test Signup Forms and Increase Conversions (Step by Step).