Splunk Add on for ServiceNow Updating Security Incidents instead of creating new

Using The Splunk Add On for ServiceNow we are generating Security Incidents. This was working correctly then suddenly stopped creating new Incidents and just updating the last incident for that alert. Each Splunk search result has a unique correlation ID and the alerts are configured with $result.correlationID$ in the alert. I've tried removing the correlation ID, recreating the search/alert will create a new Incident but then that will be updated. What should I do to ensure a new Incident is created for each search result, each time the alert is scheduled to trigger?