A PHP Error was encountered

Severity: Notice

Message: Trying to access array offset on value of type null

Filename: controllers/Login.php

Line Number: 23

Backtrace:

File: /home/siedoo/dev/psbmgl/application/controllers/Login.php
Line: 23
Function: _error_handler

File: /home/siedoo/dev/psbmgl/index.php
Line: 319
Function: require_once