PHP script '/media/public/otomilan/public/wp-content/plugins/persian-gravity-forms/includes/lib/jalali.php' is protected by SourceGuardian and requires a SourceGuardian loader 'ixed.7.4.lin' to be installed.
1) Click here to download the required 'ixed.7.4.lin' loader from the SourceGuardian site
2) Install the loader to /usr/lib/php/20190902
3) Edit /etc/php/7.4/fpm/php.ini and add 'extension=ixed.7.4.lin' directive
4) Restart the web server