A PHP Error was encountered

Severity: Notice

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

Filename: controllers/Appointment.php

Line Number: 59

Backtrace:

File: /var/www/vhosts/bookastylist.co.uk/app.bookastylist.co.uk/nodcms/controllers/Appointment.php
Line: 59
Function: _error_handler

File: /var/www/vhosts/bookastylist.co.uk/app.bookastylist.co.uk/index.php
Line: 328
Function: require_once