Google Search Console Hentry error fix

gschentry-fix-functions.php

<? php
//Fix for missing author, entry title, and updated in GSC
////add hentry data
function add_hentry_data($content) {
    $t = get_the_modified_time('F jS, Y');
    $author = get_the_author();
    $title = get_the_title();
if (is_home() || is_singular() || is_archive() ) {
        $content .= '<div class="hentry-extra" style="display:none;visibility:hidden;"><span class="entry-title">'.$title.'</span> was last modified: <span class="updated"> '.$t.'</span> by <span class="author vcard"><span class="fn">'.$author.'</span></span></div>';
    }
    return $content;
    }
add_filter('the_content', 'add_hentry_data');

Should add this to every function script!