PHP Warning

I continually find the warning below in my error log

PHP Warning: preg_match(): Unknown modifier ‘I’ in /xxxx/xxxxxxxxxx/public_html/wp-content/plugins/add-search-to-menu/public/class-is-public.php on line 1009
below is line 1009

if ( ‘1’ == $fuzzy_match && preg_match( ”
/\\b{$preg_safe_term}\\b/iu”, $table_cell ) || ‘2’
== $fuzzy_match && (preg_match( ”
/\\b{$preg_safe_term}/iu”, $table_cell ) ||
preg_match( “/{$preg_safe_term}\\b/iu”, $table_cell
)) || ‘3’ == $fuzzy_match && false !== stripos(
$table_cell, $search_term ) ) {