How to get the event in my logstash ruby filter, event.get('sessions') does not fetching sessions value

I am trying to fetch the event.get(sessions) value from my config file, but I am not getting complete thing. I am having one enum-pieline.conf which is having input from elastic search index.

input {
        elasticsearch {
                hosts => "localhost:9200"
                index => "enum_pipeline_1_sessionid_index_2"
                size => 250
                scroll => "1m"
                query => '{ "sort": ["_doc"] }'
                docinfo => true
        }
        }

filter {

    elasticsearch {
                hosts => ["http://localhost:9200"]
                index => "message_index"
                query_template => "./getSessionMsgsQuery.json"

                fields => {
                        "message" => "sessions"
                }

        }

        elasticsearch {
                hosts => ["http://localhost:9200"]
                index => "enum-sessionid-counter"
                query_template => "./lookup.json"

                fields => {
                        "additionalData" => "additionalData"
                        "lastSession" => "lastSession"
                }
        }


   ruby{
        path => "./enum-ruby-filter-2.rb"
    }
}

output{
        if [Exception] {
                elasticsearch {
                        hosts => ["localhost:9200"]
                        index => "pipeline-two-out"
                        }
        } else if [additionalData] {
                elasticsearch {
                        hosts => ["localhost:9200"]
                        index => "pipeline-two-out"
                        document_id => "%{[additionalData][doc_id]}"
                        scripted_upsert => true
                        action => "update"
                        script => '
                                ctx._source.additionalData = params.event.get("additionalData");
                                ctx._source.lastSession = params.event.get("lastSession");
                                '
 }
    } else {
                elasticsearch {
                        hosts => ["localhost:9200"]
                        index => "pipeline-two-out"
                        document_id => "%{[@metadata][updated_doc_id]}"
                }
        }

}

RUBY FILTER

def filter(event)

    begin
        print(event)
        index_name = 'message_index'
        event_doc = event.get('sessions')
        print "\n---****---\n"
        print event_doc
        print "\n---****---\n"
        #When the elasticsearch lookup returns single document
        #the returned type will be doc and if it contains multiple
        #docs the return type will be array
        if event_doc.is_a?(Hash)
            event_doc = [event_doc]
        elsif event_doc.is_a?(Array)
            event_doc = event_doc.sort_by{ |hash| hash['timestamp'] }
        end
        #event_doc = event_doc.sort_by{ |hash| hash['timestamp'] }
        doc_id = event.get('doc_id')
        print "\n---**---\n"
        print (doc_id)
        print "\n---**---\n"
        additionalData = event.get('additionalData')
        print "\n---**---\n"
        print (additionalData)
        print "\n---**---\n"
        if additionalData == nil
            sessionDoc = {}
            sessionIdCounter = 1
            recvdResponse = true
        else
sessionIdCounter = additionalData['sessionIdCounter']
            recvdResponse= additionalData['recvdResponse']
            sessionDoc = event.get('lastSession')
        end

        event_array = []

        event_doc.each { |message|
            message_type = message['MessageType']
            if message_type == 'ENUMResponse'
                sessionDoc[message_type] = message
                updated_doc_id = doc_id + '-' + sessionIdCounter.to_s
                sessionDoc['@metadata'] = {'index_name' => index_name,
                    'updated_doc_id' => updated_doc_id,
                    'doc_id'  => doc_id
                }
                sessionDoc['sessionIdCounter'] = sessionIdCounter
                event_array.append(LogStash::Event.new(sessionDoc))
                sessionIdCounter += 1
                recvdResponse = true
                sessionDoc = {}

            elsif message_type == 'ENUMRequest' and recvdResponse == false
                updated_doc_id = doc_id + '-' + sessionIdCounter.to_s
                sessionDoc['@metadata'] = {'index_name' => index_name,
                     'updated_doc_id' => updated_doc_id, 'sessionIdCounter' => sessionIdCounter,
                     'doc_id' => doc_id
                }
                sessionDoc['sessionIdCounter'] = sessionIdCounter
                event_array.append(LogStash::Event.new(sessionDoc))
                event_array.append(LogStash::Event.new(sessionDoc))
                sessionIdCounter += 1
                sessionDoc = {}
                sessionDoc[message_type] = message
            else
        recvdResponse = false
                sessionDoc[message_type] = message
            end
        }

        additionalData = {
                    'sessionIdCounter' => sessionIdCounter,
                    'doc_id' => doc_id,
                    'recvdResponse' => recvdResponse
        }
        last_doc = { 'additionalData' => additionalData, 'lastSession' => sessionDoc }
        event_array.append(LogStash::Event.new(last_doc))
        return event_array
    rescue Exception => e
        event_array = []
        event_doc = {"Exception" => e.message}
        event_doc["backtrace"] = e.backtrace.inspect
        event_array.append(LogStash::Event.new(event_doc))
        return event_array
    end

 end

In my elastic search I have 4 index are present
1. message_index--> Having response/request in it
2.enum_pipeline_1_sessionid_index_2 --> havind document id(session id)
3.counter_index & pipeline-two-out--> used for output purposes
When I am trying to debug I am not getting my session in the event.get(sessions).

OUTPUT
2022-09-14T15:07:32.956Z %{host} %{message} ---****---

---****---

------ 0x486b ------

---**---

---**--- 2022-09-14T15:07:32.972Z %{host} %{message} ---****---

---****---

------ 0x486b ------

---**---

---**---

The fields of event_doc and additionalData is empty. Please help almost spent 2 days in it already.

What I have done
Changed my ruby filter code and conf file too but no progress.