Your site is hidden with a password.
What widget are you using? Your best bet is to contact its developers. If you got the widget from the wp.org repository, click on their “support” button to post a question to them.
I included the password in my post above.
It’s a iFrame in a text widget
FB is including a “max-height” of 70px on one of the inner elements. As that’s coming from FB, you’ll need to fix it (if possible) on the facebook side. It can’t be fixed from WP.
See https://cldup.com/u_UNHwGrvVr/Apn8uk.png

I fixed it by adding px into the code