Hi,
It is because of the ajax handler is restricted from public access: https://www.4myschools.org/wp-admin/admin-ajax.php
It should be publicly accessible, as it is the core WordPress ajax handler. You may have accidentally added a firewall rule in WordFence to restrict access to the wp-admin folder. I strongly recommend not doing that, or if you must, then make sure to add all the known access points as exceptions.
