HSTS not working with Chrome

Did you configure your site config so that Apache forces SSL on all subdomains, not just example.com and www.example.com?

Also I believe that the chrome://net-inteals/#hsts only shows correct queries from sites that are preloaded and added via https://hstspreload.appspot.com/ . This explains why chrome://net-inteals/#hsts doesn't work for you.