You’re using wrong arguments for get_the_category_list
function. The function you should use for this is wp_get_object_terms
http://codex.wordpress.org/Function_Reference/wp_get_object_terms
You’re using wrong arguments for get_the_category_list
function. The function you should use for this is wp_get_object_terms
http://codex.wordpress.org/Function_Reference/wp_get_object_terms