get_categories is empty

I have the same code on 10+ websites, I can see the items are there but then WP stopped displaying… and the array is empty.

$subcategory = get_categories(array('taxonomy' => 'slide-page', 'post' => 'slide', 'hide_empty' => false, 'meta_key' => 'order', 'orderby' => 'meta_value', 'order' => 'ASC'));