Not able to access a variable in moustache template which i created

Describe the issue: I created a variable using below script to convert periodEnd and periodStart to local timezone

"script_fields": {
    "periodStartFormatted": {
      "script": {
        "source": "def sdf = new SimpleDateFormat('yyyy-MM-dd HH:mm:ss'); sdf.format(doc['@timestamp'].value.toInstant().toEpochMilli() + 8 * 60 * 60 * 1000)",
        "lang": "painless"
      },
      "ignore_failure": false
    }
  }

the new property is now seen under fields property of Extraction Response, however I am not able to access the field that was created in the moustache template. The other default fields such as @timestamp, timestamp are accessible

@msitaram I understand that you’ve created a stored script with the above syntax and now you want to access it using the moustache template. Is that correct?

@pablo Exactly, i have this field under fields property, but when i am trying to access it in moustache template, i only get to see
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