Adsense: URL must be a valid top-level domain

If you’re getting this error “URL must be a valid top-level domain” in the Adsense account while adding a new site like, http://www.sample.com

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Go to Sites -> Add site -> Enter the above URL with www like sample.com. Don’t include the Http or www.

Hurray! Your site is added and you can submit for the AdSense account on the next page.