Timestamp is no longer transferred correctly

Hello everyone,
I import values from a CSV via Logstash to Elasticsearch, whereby the timestamp is correctly determined from the name of the CSV and then the correct format is also written to Elasticsearch - e.g.: 2024-03-29T10:40:09.324934244Z
Strangely enough, I see the wrong value for the variable @timestamp in Kibana, namely the value for the execution / import of the data set. It worked fine until a few weeks ago with the same script. Does anyone have any idea what the problem could be?

Logstash Script - date part:

  # Datum und Uhrzeit aus dem CSV-Timestamp extrahieren und in @timestamp speichern
  date {
    match => ["Timestamp", "EEE dd MMM yyyy hh:mm:ss a 'CEST'", "EEE dd MMM yyyy hh:mm:ss a 'CET'"]
    timezone => "Europe/Berlin" # Setzen Sie diese auf Ihre relevante Zeitzone.
    #remove_field => ["Timestamp"]

  # Konvertiere Millisekunden zu Sekunden und kombiniere mit @timestamp
  ruby {
      code => "
        # Konvertiere @timestamp in ein Time-Objekt
        timestamp_str = event.get('@timestamp').to_s
        new_time = Time.at(DateTime.parse(timestamp_str).to_time.to_f)

        # Setze das aktualisierte @timestamp-Feld zurück
        event.set('@timestamp', LogStash::Timestamp.new(new_time))


output {
  stdout { codec => rubydebug }
  file {
    path => "/home/ai-upload/logstash.log"
    codec => "rubydebug"

    elasticsearch {
      hosts => ["http://localhost:9200"]
      index => "moderationen"

elasticsearch import python part:

# Die letzten Timestamps finden
    last_indexed = es.search(index="topics", size=1, sort={"@timestamp": "desc"})
    last_timestamp = last_indexed['hits']['hits'][0]['_source']['@timestamp']
    last_timestamp = "1900-01-01T00:00:00.000Z"

# Nachrichten abrufen, die neuer sind als der zuletzt gespeicherte Timestamp
response = es.search(index="moderationen", size=10000, _source=["_id", "text", "@timestamp"],
                         "range": {
                             "@timestamp": {
                                 "gt": last_timestamp

timestamps = [hit["_source"].get("@timestamp", None) for hit in response["hits"]["hits"]]
print("Anzahl der Timestamps:", len(timestamps))


# Verarbeiten Sie jedes Dokument mit OpenAI
for idx, document in enumerate(documents):
    word_count = len(document.split())
    char_count = len(document)
    # Ergebnisse in Elasticsearch speichern
    es.index(index="topics", document={
        "@timestamp": response['hits']['hits'][idx]['_source']['@timestamp'],
        "id": ids[idx],
        "text": documents[idx],
        "topics": extracted_topics

This is one record at my index:

I think dateparsefailure indicates a problem, but how could I find the correct log file?

The timestamp formats you have specified in the date filter's match clause does not match the format in the example document. The example document Timestamp field has the year at the end, not after the month as specified in the pattern.

Ah sorry, the filename at the example document is Mon Apr 1 05:54:51 PM UTC 2024. I´ve posted the transformed format which is delivered by the python process to elasticsearch, which is e.g. 2024-03-29T10:40:09.324934244Z.

Since this script was running correctly for months anything has changed at elastic or python.

I do not understand what you mean. The document from your index has Timestamp set to Mon Apr 1 05:54:51 PM UTC 2024. As far as I understand this is what the Logstash date filter sees and it does not match any of the timestamp formats to match.

If this was the case you would indeed get a _dateparsefailure and @timestamp would be set to the current system time, which seems to be what is happening.