Issue happening on the Operator Console
Some alarms assigned to a user - the alarm appears "assigned", in the "assigned to" column, but after a while, the "assigned" status disappears - meaning that the alarm would no longer be assigned.
Existing NAS rule to unassign such alarm
Release : Any release
Component : NAS
Customer had NAS rule that was doing the unassign.
To check this, In IM select the open alarm > right click >transaction history:
Example, check assigned to/assigned by: