my understanding is that a shelved alarm that is “Acked” and “Cleared” and become active again before the end of the shelve duration would not appear as shelved because it is a different alarm, but I have this issue that the new alarm is automatically shelved because the shelve duration has not expired.
I’m afraid that you have misunderstood the purpose of the shelving system.
My understanding is that the shelving function effectively deletes the alarm from the alarming system during the shelving period. No new alarms will be detected during this period. However, if the alarm conditions are still true at the end of the shelving period, a new alarm will become active in the alarm system.
What is it that you were trying to accomplish with the shelving feature? If you are just wanting to remove an alarm that has been Acked from a list, you might be able to filter on that property and get the behavior that you are after.