How to fix (Failed: DNS error: Host Unknown) on GSC.
Failed: DNS error: Host Unknown is an error message that shows up when google fails to index your site and without fixing these errors your post on a blog or website won’t be indexed by Google. This error occurs when google is unable to communicate with the ” www SSL certificate” or this SSL certificate has expired based on personal experience both on blogger and WordPress.
To solve this problem on WordPress, renew your Let encrypt SSL certificate and untick generates SSL certificate for “www and non-www” generate the new certificate and install it. Go to your Google Search Console (GSC) and reindex your post.
For blogger go to GSC and select another site property and try to index with that one if the first property doesn’t work. You can also Turn disable and enable your SSL certificate on blogger.