Error 500

Hi and thanks for your plugin that we use in two website.
With gloo.it We had an intrusion problem with a malware and after reinstalling a backup of our site the Salert plugin version 1.1.9 works perfectly, but from the admin dashboard we tried to go to change the side of the popup from right to left but we have an error 500 (only with Salert) and when we don’t have the error the page loads without desktop image and without “save setting” button and we don’t have the possibility to click on any tab.
We increased the php memory and uninstalled the plugin without acting on the database and then reinstalled it, but it gives the same error.
Do you have any idea what we can do?
Thanks

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