Page Builder activation.php file missing

Hi
I’m having problem with the latest plugin version installed on two of my sites both with Maskitto light theme.
Every day the sites are off and they return a 500 error. I found out that the file activation.php in inc folder keep desappearing every day. I updated everything, tryed to deactivate other plugins that may cause conflict, tryed to reinstall page builder but the problem persist. But the only way to have sites online is to upload the file every day.
Any idea of what is happening?
my sites http://gliamiciditeo.it http://accademiamusicalestradella.it