尝试更新单行时Dialogflow实体被覆盖

Question

当我尝试使用实体api更新dialogflow中的实体列表时，整个列表将被覆盖，我丢失了旧记录。 我该如何处理这个问题？

以下是我在项目中执行的api调用：

var request = require("request");
        var url = "https://api.dialogflow.com/v1/entities/b56efdf4-09c8-402e-96ee-8185ef4c0a5b";
        var send_id;
        var send_name;

        //channel
        var auth_token = "Bearer dev_token"; 
        var headers = {
         "Authorization":  auth_token,
         "Content-Type" : "application/json"
        }



         var body = {
            "automatedExpansion":true   , 
            "isOverridable":false,
            "entries": [
               {
                  "synonyms": [name] ,
                  "value": channel_name
               }
            ],
            "name":"new"
         }

         request.put({
            "url": url,
            "headers": headers,
            "body": JSON.stringify(body)
         }, (err, response, body) => {

            if (err) {
               reject(err);
            }
            ///resolve(JSON.parse(response.body));
            console.log("response: "+ response.body);
         });