Kibana Discover not showing data for any time range

Elastic Stack Kibana
10

I followed this:

And I tried to create an ingest pipeline like following for re-indexing:

POST _ingest/pipeline/_simulate
{
  "pipeline" :{
  "description": "date pipeline ",
  "processors": [
    {
        "script": {
          "source": """
             SimpleDateFormat format = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z");
             ctx._source['@timestamp'] = format.format(format.parse(ctx._source['@timestamp']));
          """
        }
    }
  ]},
  "docs": [
    {
      "_index" : "temp-http",
      "_type" : "_doc",
      "_id" : "ROhMSGgBnWcQaR3FnxJ2",
      "_version" : 2,
      "found" : true,
      "_source" : {
        "response_time" : "175",
        "@timestamp" : "Sun, 13 Jan 2019 17:40:07 GMT"
      }
    }
  ]
}

But it gives "class java.lang.Integer cannot be cast to class java.lang.Long (java.lang.Integer and java.lang.Long are in module java.base of loader 'bootstrap')".
What should I change to make this work?