Deleting page problematic

Upon deleting a page I get an error message which refers to the passster plugin.

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class ‘passster\PS_Admin’ does not have a method ‘password_lists’ in …/wp-includes/class-wp-hook.php on line 286 Warning: Cannot modify header information – headers already sent by (output started at …/wp-includes/class-wp-hook.php:286) in …/wp-includes/pluggable.php on line 1251 Warning: Cannot modify header information – headers already sent by (output started at …/wp-includes/class-wp-hook.php:286) in …/wp-includes/pluggable.php on line 1254

The page gets deleted but you have to start WP again.