A PHP Error was encountered

Severity: Notice

Message: Undefined index: HTTP_REFERER

Filename: controllers/Login.php

Line Number: 17

Backtrace:

File: /var/www/vhosts/myaseentravel.com/httpdocs/application/controllers/Login.php
Line: 17
Function: _error_handler

File: /var/www/vhosts/myaseentravel.com/httpdocs/index.php
Line: 266
Function: require_once