It seems that I can fix this weird issue, when I do the following:
update_field(‘some_json’, json_encode($array), $post_id);
update_post_meta($post_id, ‘_some_json’, ‘some_json’, ‘field_some_json’);
After renaming the Value from “field_some_json” to “some_json”, I can access it with get_field(‘some_json’); again.
