### 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
Fuzziness fuzziness,
            int prefixLength,
            int maxExpansions,
            boolean transpositions,
            SearchExecutionContext context
        ) {
            throw new UnsupportedOperationException(
                "[fuzzy] queries are not currently supported on keyed " + "[" + CONTENT_TYPE + "] fields."
            );
        }
        @Override
        public Query regexpQuery(
            String value,
            int syntaxFlags,
            int matchFlags,
            int maxDeterminizedStates,
            MultiTermQuery.RewriteMethod method,
            SearchExecutionContext context
        ) {
            throw new UnsupportedOperationException(
                "[regexp] queries are not currently supported on keyed " + "[" + CONTENT_TYPE + "] fields."
            );
        }
        @Override
        public Query wildcardQuery(
            String value,
            MultiTermQuery.RewriteMethod method,
            boolean caseInsensitive,
            SearchExecutionContext context
        ) {