Shortcode php erroe

i get this error suddenly .. is shortcode line 58 ..

Warning: explode() expects parameter 2 to be string, array given in /home/igsgeek/public_html/wp-content/themes/Magazon/st-framework/settings/shortcode.php on line 58 .. lines 56 – 60 below

if($list_cate>0){
// $args[‘category__in’] = array($cats);
$args[‘category__in’] = explode(‘,’, $list_cate);

}

so what is the problem in this line . please give soem solution