Notice: Undefined index: appId in /home/lions/public_html/wp-content/plugins/wp

Hello,

What is the below error about?

Notice: Undefined index: appId in /home/lions/public_html/wp-content/plugins/wp-embed-facebook/lib/base_facebook.php on line 232

WP : 4.3.1
wp-embed-facebook : 2.0.3

You can find the full error with call stack here:

https://www.lionsclub-valdeurope.org/notre-club-2/facebook/

Thanks

Hans

https://www.ads-software.com/plugins/wp-embed-facebook/