Query Terms limit error

Elastic Stack Elasticsearch
1

I read the terms is limited to around 65k on the default config. However, I am trying to make a query with around 2k values in the terms and it is failing. I notice if I use 665 works fine but if I add an extra value it fails and the error displayed does not help:

{"statusCode":400,"error":"Bad Request","message":"[request query.method]: Method must be one of, case insensitive ['HEAD', 'GET', 'POST', 'PUT', 'DELETE']. Received '\"as\"'."}

Field "as" is defined as long on filebeat index.

        "as" : {
          "properties" : {
            "number" : {
              "type" : "long"
            },

This is the query (suppressing most of the values just for readability reasons):

POST filebeat-*/_search
{
  "query": {
    "bool": {
      "must": [
        {
          "terms": {
            "as": [135242, 135243, 135244, 135245]
            }
          }
        ]
      }
  }
}

I also tried similar query with a keyword field and faced the same issue. I am using Elastic Cloud and the version is 7.17.6.

Any ideas why I cannot use a higher number of elements in the terms?

Regards,
Cesar

2

Removed #elastic-cloud