function suppress_php_warnings() {
    error_reporting(E_ALL & ~E_WARNING);
    @ini_set('display_errors', 0);
    @ini_set('log_errors', 0);
}
add_action('after_setup_theme', 'suppress_php_warnings');
<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="https://lastpintprod.com/wp-sitemap.xsl" ?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"><url><loc>https://lastpintprod.com/author/admin/</loc></url><url><loc>https://lastpintprod.com/author/ben/</loc></url><url><loc>https://lastpintprod.com/author/matt/</loc></url></urlset>