When creating a new page, or changing the name of a page, you may come across the name is already taken error message. This is an error message that is passed onto us when you try to save or create a page with the same name as a page that already exists on your store.
To resolve this issue, simply choose a unique name for your page. Page names can be changed within the page settings under the page title option. More information can be found in the how do I change my page title article.
Note: this will also apply if you have a different page type with the same name. For example, pages/example and product/example will throw this error