Whats causing this problem in ACF when running php 7.4?

Question

I recently updated my site to php 7.4. It's running a custom build wordpress theme using ACF Pro v 5.5.5. However, once updated i get this error:

Notice: Trying to access array offset on value of type bool in wp-content/plugins/advanced-custom-fields-pro/api/api-template.php on line 503

The snippet it refers to looks like this:

    acf_add_loop(array(
        'selector'  => $selector,
        'name'      => $field['name'], // line 503
        'value'     => $value,
        'field'     => $field,
        'i'         => -1,
        'post_id'   => $post_id,
        'key'       => $key
    ));

I have googled this for hours without really find a solution that works. Right now i don't even know how to go further. Any suggestions? Anyone had this problem? Since it refers to ACF itself i believe it could be some php stuff in 7.4 that's not compatible, but i have really no idea.

Answer 1

Solved by updating to the lastest ACF (5.9.5).