Identify issue for :
console admin-ajax.php 500 error
OR
any unknown issues in WORDPRESS
https://wordpress.org/support/topic/admin-ajaxphp-500-error-2
please add following lines to wp-config.php file.
define(‘WP_DEBUG’, true);
define( ‘WP_DEBUG_LOG’, true );
define( ‘WP_DEBUG_DISPLAY’, false );
Please add those lines before.
/* That’s all, stop editing! Happy blogging. */
This will create a debug.log file in /wp-content/ folder.