In wp-config file find line define(‘WP_DEBUG’, false); Comment out this, and add the lines given below to get more detailed error reporting from your WordPress site. Be careful to revert the same from the production server, do it for development purpose only.

// define('WP_DEBUG', false);
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true); // Log errors in /wp-content/debug.log
define('WP_DEBUG_DISPLAY', false);
@ini_set('display_errors', 0);