The Types plugin is making this about 10x harder than it needs to be, you’ll have to look through their documentation on the issue, but from what I can tell they don’t store items in the postmeta table in a straightforward way. I created a simple field with the plugin in a sandbox env and the meta_key for a field I named data was wpcf-data. You may want to take your post ID and do this in your DB:
SELECT * FROM wp_postmeta WHERE post_id = NNNN;
where NNNN is your post ID. You may see a wpcf-authorinfo key, that is likely then the key you should be passing to get_post_meta:
echo get_post_meta(get_the_ID(), 'wpcf-authorinfo', TRUE);