这是我的实体：

public class RecentTransactionBo {

    @JsonProperty("timestamp")
    @Field(type = FieldType.Date, format = DateFormat.basic_date_time)
    @Id
    @Temporal(TemporalType.DATE)
    private Date creationDate;
    private List<String> transactionId;

}

我正在对它进行排序操作：

Iterable<RecentTransactionBo> recentTransactionBoIterable = recentTransactionDao.findAll(Sort.by(Sort.Direction.DESC, "creationDate"));

我得到以下错误：

2020-09-08 02:42:29.116 ERROR 7116 --- [nio-8090-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.data.elasticsearch.UncategorizedElasticsearchException: Elasticsearch exception [type=search_phase_execution_exception, reason=all shards failed]; nested exception is ElasticsearchStatusException[Elasticsearch exception [type=search_phase_execution_exception, reason=all shards failed]]; nested: ElasticsearchException[Elasticsearch exception [type=illegal_argument_exception, reason=Text fields are not optimised for operations that require per-document field data like aggregations and sorting, so these operations are disabled by default. Please use a keyword field instead. Alternatively, set fielddata=true on [creationDate] in order to load field data by uninverting the inverted index. Note that this can use significant memory.]]; nested: ElasticsearchException[Elasticsearch exception [type=illegal_argument_exception, reason=Text fields are not optimised for operations that require per-document field data like aggregations and sorting, so these operations are disabled by default. Please use a keyword field instead. Alternatively, set fielddata=true on [creationDate] in order to load field data by uninverting the inverted index. Note that this can use significant memory.]];] with root cause

    org.elasticsearch.ElasticsearchException: Elasticsearch exception [type=illegal_argument_exception, reason=Text fields are not optimised for operations that require per-document field data like aggregations and sorting, so these operations are disabled by default. Please use a keyword field instead. Alternatively, set fielddata=true on [creationDate] in order to load field data by uninverting the inverted index. Note that this can use significant memory.]

我的刀是这样的。

@Repository
public interface RecentTransactionDao extends ElasticsearchRepository<RecentTransactionBo, Date> {

}

我该如何解决这个问题？我犯了什么错误？我使用的是7.8.1版