If your website page title is not displaying as per your WordPress SEO then you probably have an issue with your Theme header.php setup. Largely this is down to bad WordPress website development which typically manifests in the page title being manually typed, rather than using the correct wp_title() format for WordPress and your SEO plugin (like Yoast SEO, Premium SEO) to target for SEO updates. If the SEO title on all of your posts/pages/custom posts is the same, or not what you are inputting into your SEO plugin and your SEO rankings have plummeted, then you are probably affected. To fix this go ahead and open your WordPress site’s header.php file and look at the ‘head’ tag at the top of the file for:-
<head> <title>SEO plugins can't target this manually inputted title</title> </head>
Replace the above with:-
<head> <title> <?php wp_title('', true,''); ?> </title> </head>
Now the SEO plugin can use the wp_title WordPress hook to inject the correct SEO page titles into the Page / Post / Custom Post Titles; so problem solved and you can now get your SEO back on track!