A PHP Error was encountered

Severity: 8192

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

Filename: campaign_dashboard/campaign_dashboard_sidebar.php

Line Number: 8

Backtrace:

File: /home/tadaang/public_html/application/user/views/campaign_dashboard/campaign_dashboard_sidebar.php
Line: 8
Function: substr

File: /home/tadaang/public_html/application/user/views/campaign_dashboard/campaign_dashboard.php
Line: 6
Function: view

File: /home/tadaang/public_html/application/user/controllers/Campaign_dashboard.php
Line: 22
Function: view

File: /home/tadaang/public_html/index.php
Line: 293
Function: require_once