Your URL protocol of that site is HTTP, not HTTPS. I checked your site.
To move to HTTPS requires a server setting, it is not a WordPress Admin setting. WordPress admin settings, have to follow the server settings.
If you get access issues or HTTP is not showing or HTTPS is not showing, then you need to contact your hosting service. Your HTTP/HTTPS protocol is managed at their end.
By the way, Google has encouraged all websites to move to HTTPS protocol, which you should and most hosting services provide a free version of SSL which is what gives you HTTPS. Contact your hosting service for more information.
Also, any time you change things like URL protocols on a website, clear your browser cache before testing it.
Google & HTTPS requirements:
1. https://support.google.com/webmasters/answer/6073543?hl=en
2. https://www.searchenginejournal.com/google-sets-https-deadline/236225/