Global Site Tag (aka. GTag) is responsible for sending data from your website to Google Ads for remarketing and performance enhancement purposes. This error happens when you don't have a proper remarketing setup on your website. Follow our [Google Ads - Shopify playbook](https://docs.analyzify.app/playbook-google-ads-pixels-shopify) to make sure your settings are correct. You can also contact Analyzify's support team if you are an existing client.