Sort custom post type by most current date picker

Question

I'm trying to sort custom post type made with ACF plugin by most current date. Ideally future most current post should be first. Currently, I'm sorting by date, which gives me the earliest post as the first post.

Here is my code.

$loop = new WP_Query( array( 
    'post_type'             => 'events', 
    'posts_per_page'        => -1,
    'meta_key'              => get_sub_field( 'date_start' ),
    'orderby'               => 'meta_value_num',
    'order'                 => 'ASC'
) ); 

Here is the screenshot of my website to make things clear.

I have tried this post to no avail https://stackoverflow.com/questions/28951370/sort-wp-query-by-acf-datepicker

It seams that my meta_query is not properly setup. This is the meta_query that I tried.

'meta_query' => array(
    array(
        'key' => get_sub_field( 'date_start' ),
        'compare' => '>=',
        'value' => current_time('Ymd'),
        )
),

note: for some reason I have to do get_sub_field('date_start') plain 'date_start' doesn't return any results.

Answer 1

So thanks to Jacob Peattie and his helpful comments I was able to resolve this issue.

meta_key was part of the group, but it wasnt prefixed by a group key. So, something like this totally works for me: group_field_sub_field. So changing that in both arrays did the trick.