A PHP Error was encountered

Severity: Notice

Message: Undefined variable: device_name

Filename: helpers/global_helper.php

Line Number: 150

Backtrace:

File: /var/www/html/pceuat/application/helpers/global_helper.php
Line: 150
Function: _error_handler

File: /var/www/html/pceuat/application/views/layouts/navbar.php
Line: 33
Function: check_device_type

File: /var/www/html/pceuat/application/views/layouts/main.php
Line: 20
Function: view

File: /var/www/html/pceuat/application/controllers/Agenda.php
Line: 17
Function: view

File: /var/www/html/pceuat/index.php
Line: 322
Function: require_once