The url_response probe is generating alarms under the wrong model. It created a new EventModel type with URL domain instead of using configured source. Pre-Prod environment is showing the expected (good) behavior with the same version of the probe and configuration that is used in PROD. In PROD, it seems to be that the probe is not sending the IP/HostName attribute value which may change the way the event is matched to the model.
Release : 8.51
Component : UIM - URL_RESPONSE v4.46
After deselecting the "Alarm when substring found" option in the url_response GUI (since no string was being specified), in both pre-prod and PROD, the Hostname/IP address was then displaying as expected not only in pre-PROD but also PROD when you viewed the alarm in Spectrum.
Furthermore, as per suggestion the customer removed the existing url_response profiles, deactivated both probes and reconfigured the profiles from scratch.
The IP address was displaying in PRE-PROD and PROD which allows the alarm to be properly attached to the correct model in Spectrum.