Forminator’s CSS style cannot be loaded because your website’s address is configured in WordPress to use HTTP instead of HTTPS. This may cause some web content, including Forminator forms, to display incorrectly.
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To fix this, you need to update your WordPress site url to HTTPS. You can do this by going to your WordPress admin dashboard, then Settings > General, and change both the ‘Site Address (url)’ and ‘WordPress Address (url)’ to use https:// at the start
After that you can use .htaccess rule to force all traffic to https: