Hi Amit,
the name of the CI an Alert is attached to is always specified when the CI is created, not as part of the Alarm.
The Alarm only knows about the internal ID of the CI it shall be attached to.
Thus, modifying the Label of the CI has to be done when the CI is created, e.g. in the extensions of the Item classes (where you already looked).
It cannot be done in the Alert class.
You have to update the relevant Item class and then reload all the CIs to get the fresh label.
MichaelBoehm