Hi,
Sorry for misunderstanding
First, please update the theme to latest version 4.0.4 and the afferent plugins, you can check the plugin update status from wp-admin -> appearance -> install plugins.
If this is useless please enable wp debug by going to ftp in root directory of your wp install open wp-config.php look for define( ‘WP_DEBUG’, false ); and change it to true and after this line add this
define( 'WP_DEBUG_LOG', true );
WP_DEBUG_LOG is a companion to WP_DEBUG that causes all errors to also be saved to a debug.log log file inside the /wp-content/ directory. This is useful if you want to review all notices later or need to view notices generated off-screen (e.g. during an AJAX request or wp-cron run).
Repeat the described actions and then check the debug.log file and let me know what error appears.
If this is useless please try to deactivate additional plugins except Visual Composer,K-elements,buddypress,paid memberships pro and revolution slider.
Cheers
Radu