Do you see any messages when you use WP_DEBUG?
The debug setting will usually display various notices/warning/errors that are typically hidden from being displayed (site wide). It’s located within the wp-config.php file.
To turn it on…
Open the file, look for
define('WP_DEBUG', false); and set it to true like
Add the snippet above if the setting doesn’t exist already.
After testing be sure to remove the line or set it to false