SEO Backlink - Comments are not being approved?

What is the solution can any suggest me some guidelines...

Maybe sites are not moderated like before? Check if there any recent comment approved on the pages or not. If not that mean's owner is not active anymore. If you see there are new comment's approved that means you have to work properly. Read the approved comments what they read and you will understand why those are approved. Comment's like "Nice article. It's a good read" are not create any value for the site owners anymore. It has to be creative and engaging.