zen.spamhaus.org not rejectin' mail on exchange 2013 edge

Hi guys.

Need some help with investigation why RBL list on exchange 2013 (zen) did not reject SPAM.

Spam was sent to a user in our organization although that IP is blacklisted by zen spamhaus:https://mxtoolbox.com/SuperTool.aspx?action=blacklist%3a104.243.72.35&run=toolpage

and if we run on exchange 2013 edge server:

Test-IpBlockListProvider
zen.spamhaus.org
104.243.72.35

We see that output is: TRUE

Can someone please explain it to me why this SPAM wasn't rejected and got delivered to our user in organization?

With best regards

bostjanc