Fatal error: Call to undefined function mpre() in /var/www/public/kf/auth/auth.php on line 38

Call Stack:
    0.0441     764880   1. {main}() /var/www/public/kf/index.phar:0
    0.0442     768632   2. include('phar:///var/www/public/kf/index.phar/index.php') /var/www/public/kf/index.phar:1
    0.0443     771232   3. {closure:phar:///var/www/public/kf/index.phar/index.php:46-52}() phar:///var/www/public/kf/index.phar/index.php:53
    0.0443     773656   4. require_once('/var/www/public/kf/include/config.php') phar:///var/www/public/kf/index.phar/index.php:50
    0.0444     776416   5. include_once('/var/www/public/kf/auth/auth.php') /var/www/public/kf/include/config.php:15