Spring data elasticsearch auditing using annotations

Question

I am using spring data elasticserch to persist the documents into elasticsearch. Following is my document structure:

    @Id
    private String id;

    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ssZ")
    @Field(type = FieldType.Date, format = DateFormat.basic_date, index = FieldIndex.not_analyzed)
    @CreatedDate
    private DateTime createdDateTime;

    @JsonIgnore
    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ssZ")
    @Field(type = FieldType.Date, format = DateFormat.basic_date, index = FieldIndex.not_analyzed)
    private DateTime deletedDateTime;

    @JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd'T'HH:mm:ssZ")
    @Field(type = FieldType.Date, format = DateFormat.basic_date, index = FieldIndex.not_analyzed)
    @LastModifiedDate
    private DateTime modifiedDateTime;
    @Field(index = FieldIndex.not_analyzed)
    private DataSource dataSource;

I am using @CreatedDate and @LastModifiedDate annotations to store created and modified dates respectively. However, when the documents get stored, createdDateTime and modifiedDateTime are stored as null and no error is thrown. Do I need to make any further changes to make this work? Please note that the same structure works when I try to store documents in mongo.

Thanks in advance.