用Java更新Trello卡的自定义字段

我试图更新Trello卡中的自定义字段，但在响应中得到

404

到目前为止，我所尝试的：

try (CloseableHttpClient httpClient = HttpClients.createDefault()) {
        MyUtils myUtils = new MyUtils();
         HttpPost post = new HttpPost("https://api.trello.com/1/cards/" + CARD_ID + "/customField/" + CUSTOMFIELD_ID + "/item");

        List<NameValuePair> urlParameters = new ArrayList<>();
        urlParameters.add(new BasicNameValuePair("key", TRELLO_KEY));
        urlParameters.add(new BasicNameValuePair("token", TRELLO_TOKEN));
        urlParameters.add(new BasicNameValuePair("value", "{'text': 'this is a new string'}"));
                   
        post.setEntity(new UrlEncodedFormEntity(urlParameters, "UTF-8"));
        try (CloseableHttpResponse response = httpClient.execute(post)) {
            int responseCode = response.getStatusLine().getStatusCode();                
            System.out.println("response from customField = " + responseCode);
        }

    } catch (UnsupportedEncodingException e) {
        e.printStackTrace();
    } catch (IOException | ParseException e) {
        e.printStackTrace();
}

及

我错过了什么？ 多谢各位

urlParameters.add(new BasicNameValuePair("text", "hello"));

urlParameters.add(new BasicNameValuePair("value", "hello"));