A PHP Error was encountered

Severity: 8192

Message: substr(): Passing null to parameter #1 ($string) of type string is deprecated

Filename: libraries/Api_config.php

Line Number: 42

Backtrace:

File: /var/www/html/application/libraries/Api_config.php
Line: 42
Function: substr

File: /var/www/html/application/core/SIMS_Controller.php
Line: 263
Function: check_token

File: /var/www/html/application/core/SIMS_Controller.php
Line: 20
Function: app

File: /var/www/html/application/controllers/Dashboard.php
Line: 5
Function: __construct

File: /var/www/html/index.php
Line: 327
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: Cannot modify header information - headers already sent by (output started at /var/www/html/system/core/Exceptions.php:272)

Filename: helpers/url_helper.php

Line Number: 565

Backtrace:

File: /var/www/html/application/libraries/Api_config.php
Line: 46
Function: redirect

File: /var/www/html/application/core/SIMS_Controller.php
Line: 263
Function: check_token

File: /var/www/html/application/core/SIMS_Controller.php
Line: 20
Function: app

File: /var/www/html/application/controllers/Dashboard.php
Line: 5
Function: __construct

File: /var/www/html/index.php
Line: 327
Function: require_once