Monetag tags do not work for websites containing:
​blogspot.com
​wordpress.com
​wix.com
​weebly.com
and other free hosted domain name in the URL.

If you wish to monetize a website based on any of the platforms mentioned, you shall purchase a domain from a DomainRegistrar that will register your domain name and host it on their server. Wordpress and Blogger also offer hosting services for your own domain at a monthly fee.
After buying your own domain you can add and verify your site with Monetag.