You can use Administration > Event Processing > Automation > Time-Based Event Automation.  See the "Close Old Events" example.

It has a option for Groovy script, but where can we get that script which will fulfil this requirement? I tried below script, but its not working

import com.hp.ov.nms.*
import java.text.SimpleDateFormat
import java.util.concurrent.TimeUnit

// Define the time threshold (15 minutes)
def timeThreshold = 15 * 60 * 1000 // 15 minutes in milliseconds

// Get the current time
def currentTime = System.currentTimeMillis()

// Define the date format for parsing the received time
def dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")

// Function to convert a date string to milliseconds
def parseDateToMillis(String dateStr) {
try {
return dateFormat.parse(dateStr).getTime()
} catch (ParseException e) {
e.printStackTrace()
return 0
}
}

// Fetch all open events
def openEvents = Event.getEvents([status: "Open"])

openEvents.each { event ->
def receivedTime = event.getReceivedTime()
def receivedTimeMillis = parseDateToMillis(receivedTime)

if (currentTime - receivedTimeMillis > timeThreshold) {
// Close the event
event.close("Automatically closed due to 15-minute inactivity")
println("Event ${event.getId()} closed due to 15-minute inactivity.")
}
}

Hello,

Looks like you are trying to import a NNMi package.

If you need a groovy script to do this, there are a number at the Market Place (https://www.microfocus.com/marketplace/itom/category/all) where you might find one that might be a starting point.  Else, you may need to contact Opentext Professional Services or a Partner to write the script for you.  OBM is event driven, so you'll need something which looks at open events every minute or so, and checks if the event can be closed. 

Sorry, I don't know/I hope you get a better answer.