Hello,
Usually the problem is the lack of memory on the server.
Please follow the instructions in this documentation to activate debug in your site to see any PHP errors recorded that can provide insight on to whats going on. Please reply with a link to debug.log file. If you are not able to do this please send us FTP access to your site so we can do this for you.
Hello,
Thank you for your great suggestion, at the moment it is not supported. However please create a new ticket and select Feature Request as category so others can vote on your idea and get it moved into development faster. OR You can send us a customization job request by creating a new ticket in here and selecting Customization Request as the category.
The thing is that even WordPress doesn’t allow you to do this for Posts:

Hello,
Thank you for your messages, I am going to assign this ticket to Ashan and he will be able to take it from here and find you a solution. Please allow some time for him to get back to you, we greatly appreciate your patience and thank you for being a eventon customer! Also please disable any IP blocking on your site if there are any.
Hello,
The same on dev2: http://dev2.myeventon.com/events/transplantation-and-cellular-therapy-meetings/
I changed event’s date. canceled it and didn’t receive any emails.
Hello,
Unfortunately, they aren’t available in WooCommerce in any form and you cannot use them in Woo, I am afraid. Please check https://docs.myeventon.com/documentations/set-variable-prices-tickets/
Please check for latest versions of add-ons from here Your issue might be related to an older version you are running and we might have resolved this already in the newer version update. If you are on latest version of our software and the issue still persist please let us know.
To update eventon addons: You can download latest eventon addons from myeventon > my account. Then you can go to your website, deactivate old addon and install new one and activate then delete the old addon. This link will further explain the process. Also you can follow us on twitter to get real-time announcements on updates!

I try to send a screenshot, but it is not shown here. Did you get it?
Please change it to this:
define(‘WP_DEBUG’, true);
define(‘WP_DEBUG_LOG’, true);
define(‘WP_DEBUG_DISPLAY’, false);
/* That’s all, stop editing! Happy blogging. */
/** Absolute path to the WordPress directory. */
if ( !defined(‘ABSPATH’) )
define(‘ABSPATH’, dirname(__FILE__) . ‘/’);
/** Sets up WordPress vars and included files. */
require_once(ABSPATH . ‘wp-settings.php’);