The customer/action users on the frontend creates a new event/edits one of his events. He enters an URL into the Learn-More-Link field.
Instead of the URL-data beeing saved to the event, the event is saved with data from the "open-in-a-new-window YES/NO Button". In the backend the event shows the saved URL as "http://yes" or "http://no". The URL the user entered is lost.
This was introduced with your recent update of action-user. It can be temporarly fixed by commenting out:
/* echo EVO()->elements->get_element(array(
'type'=>'yesno_btn',
'label'=> evo_lang_get('evoAUL_lm1', 'Open in new window', $lang, $opt_2),
'value'=> $default_val,
'id'=> $__field_id
)); */
in line 740 of includes/form/class-form.php
Here is an example in the pic.

Hi Andrea,
Please send us wp-admin access to your site as a private message for us to further assist your situation.
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.