phalconPHP database Transactions fail

I have developed a website using PhalconPHP. the website works perfectly fine on my local computer with the following specifications: PHP Version 7.0.22 Apache/2.4.18 PhalconPHP 3.3.1 But recently I have migrated to a new VPS. with cPanel: CENTOS 7.4 vmware [server] cPanel v68.0.30 PHP Version 5.6.34 (multiple versions available, this one selected by myself) PhalconPHP 3.2.2 On the new VPS my website always gives me Error 500. in my Apache Error logs file: [cgi:error] End of script output before headers: ea-php70, referer: id ASC")->execute(); !!! but changing id to fname fixes the problem: !!! $this->view->files = Patients::query()->orderBy("fname ASC")->execute(); or even the following code throws error 500: $user = Users::findFirst(array( "conditions" => "id = :id:", "bind" => array("id" => $this->session->get("userID")) )); but again if I search by string fields there is no problem. is there a problem with the compatibility of PhalconPHP and MariaDB?