### Elasticsearch Version

8.8.0-SNAPSHOT

### Installed Plugins

_No response_

### Java Version

_bundled_

### OS Version

MacOS

### Problem Description

API when called is returning invalid response, on the same data terms aggs query runs fine 

![image](https://user-images.githubusercontent.com/3505601/220749805-ddf0d735-60d5-4e45-85bf-941ea3076a3f.png)


When run as aggs query 

![image](https://user-images.githubusercontent.com/3505601/220764360-49f7b648-8b15-43cf-afe2-01bd62e8ebc5.png)


### Steps to Reproduce

Queries are mentioned above ^^

### Logs (if relevant)

_No response_
server/src/main/java/org/elasticsearch/index/mapper/flattened/FlattenedFieldMapper.java
);
        private final Parameter<Integer> ignoreAbove = Parameter.intParam(
            "ignore_above",
            true,
            m -> builder(m).ignoreAbove.get(),
            Integer.MAX_VALUE
        );
        private final Parameter<String> indexOptions = TextParams.keywordIndexOptions(m -> builder(m).indexOptions.get());
        private final Parameter<SimilarityProvider> similarity = TextParams.similarity(m -> builder(m).similarity.get());
        private final Parameter<Boolean> splitQueriesOnWhitespace = Parameter.boolParam(
            "split_queries_on_whitespace",
            true,
            m -> builder(m).splitQueriesOnWhitespace.get(),
            false
        );
        private final Parameter<Map<String, String>> meta = Parameter.metaParam();
        public Builder(String name) {
            super(name);
        }
        @Override
        protected Parameter<?>[] getParameters() {
            return new Parameter<?>[] {
                indexed,
                hasDocValues,
                depthLimit,
                nullValue,
                eagerGlobalOrdinals,
                ignoreAbove,
                indexOptions,
                similarity,