Email Library

Dear all,
I hope you are fine. My name is Murat and I'm here to learn and get some help on codeigniter. I'm someone with very basic coding skills.
I've been requested to correct a problem on an codeigniter application. System suddenly stop to send cron jobs notifications and email are not sent using the configuration under config/email.php but the server (!)...

I tried to look everywhere and I see everytime I have a code for mail sending it refers to $this->load->library('email'); or $this->load->helper('email');
I checked in Library Folder and Helper Folder and dont have any email configuration.
Do you have any idea how can I solve this?