We have a Citrix environment with Netscaler 10.5. All of our Netscalers were added in NPM using SNMP (we do not have SAM).
Recently, we added the UnDP "sslDaysToExpire" (OID 1.3.6.1.4.1.5951.4.1.1.56.1.1.5) and the UnDP "sslCertKeyName" (OID: 1.3.6.1.4.1.5951.4.1.1.56.1.1.1) to know when the SSL certificate of our Netscalers expire directly in NPM.
The info is shown in a widget (Tabular Universal Device Poller) of each Node like so:

Now, I want to create an Alert to send and email when the UnDP sslCertKeyName Current Value is at 30 or less. here is how I configured the Alert :

The problem is: the alert is not working. It is supposed to trigger for at least 5 certificate (the ones that have 0 days to expire).
What I am doing wrong ? Can we created an Alert based on an UnDP value ?
*** NPM version: 2019.4