Even though you have an SSL certificate for your website, your visitors will not use HTTPS if HTTPS:// connection is not forced.
You can simply fix that following these steps:
- Open your hPanel;
- Click on SSL at the top of the page (available if you already have your SSL certificate);
- Click on Manage;
Select Force HTTPS!
...aaand you're done!
IMPORTANT: If you do not have a valid SSL certificate installed but forced the HTTPS:// your website can become inaccessible. To make sure, that everything will be working correctly, simply access your website by typing "https://" in front of your web address manually before configuring the steps above.
Note: If you are having mixed content issues, please check the mixed content guide, or this one if you are using WordPress.