The error message you are seeing means that Google is unable to index your website because it has been instructed not to do so. There could be a few reasons why this is happening, even if you have already unticked the “Discourage search engines” option in WordPress settings and checked Yoast settings.
One possible reason is that your site’s robots.txt file might be blocking search engines from crawling certain pages or sections of your site. You can check your site’s robots.txt file by going to “yoursite.com/robots.txt”. If you see any instructions that are blocking search engines, you can modify the file to allow them access.
Another possibility is that there is a plugin installed on your site that is blocking search engines. You can try deactivating your plugins one by one to see if any of them are causing the issue.
It’s also possible that your site was previously indexed with a “noindex” directive, which is still being honored by Google. You can check this by searching for your site on Google and looking for the message “A description for this result is not available because of this site’s robots.txt” or “This site may be filtered by SafeSearch”. If you see either of these messages, it’s possible that Google is still honoring a previous noindex directive. In this case, you can request a re-indexing of your site using Google Search Console.
I hope this will work for you too as i have applied these steps in my clients site TrackHub and the problem resolved.