Facebook Registration Confirmation email blocked by ISPConfig3

Hello Experts,
Today, I tried to register a new user account on Facebook. As usual, they will send me a confirmation email to authenticate my registration email address <[email protected]> hosted on my own small ISPConfig3 server.
However, I do not receive email sent from Facebook. So I checked my ISPConfig email log and found these log lines.

How do I correct it? I need new Facebook account to promote my small web site. Please help.

My OS is Ubuntu 24.04, ISPConfig 3.2.12p, Nginx 1.24.

 

Simply don't use zen.spamhaus.org as RBL.
The days of blocking spam with RBLs is over, especially if you use a Rspamd setup

 

Yes, I removed the zen.spamhaus.org entry from ispconfig3 and facebook emails can pass through. Thanks.