ScriptRunner groovy error: No such property: event for class

groovy.lang.MissingPropertyException: No such property: event for class: Script764

Not able to catch issue in IssueCreated event while Script Listener from ScriptRunner is used.

Issue issue = event.issue OR event.getIssue()

Trying to capture issue which fires the event.

what you are trying to do? can you share your script?

normally in postfunctions, validators and conditions we will get issue object as follows
Issue issue = issue or MutableIssue issue = issue

Using this in Script Listener which comes with ScriptRunner. Even in Script Console none of this works.