Strict Standards bug error

With debugger on, I’m getting the following error:

Strict Standards: CWS_WP_Help_Plugin and WP_Help_Plugin_Structure define the same property ($instance) in the composition of CWS_WP_Help_Plugin. This might be incompatible, to improve maintainability consider using accessor methods in traits instead. Class was composed in /home/tennessee/www/www/wp-content/plugins/wp-help/classes/plugin.php on line 721