Unable to trigger an email notification once the SR Is assigned to the queue

Summary:

We have used the below script but it doesn't send any notification, please suggest.

Trigger: AfterTransactionPosted

if (isAttributeChanged('QueueId') && AssigneeResourceId == null) {

try {

def messageText = 'HR Help Desk Request ${SrNumber} has been assigned to a queue ${QueueId}.'
   
 if (QueueId) {

        def map = new HashMap()

        map.put("Channels", ["ORA_SVC_BELL"])

        map.put("MessageText", messageText)

        map.put("RecipientQueueId", QueueId)


        adf.util.sendNotification(adf, map)

        println("Notification sent to all members of QueueId: " + QueueId)

    } else {

        println("QueueId is null. No queue notification sent.")

    }


} catch (e) {

    println("Error sending queue assignment notification: " + e)

    e.printStackTrace()

}
}

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