cant upload files

// openai
// To use dotenv, you need to add the "io.github.cdimascio:dotenv-kotlin:version"
// dependency. Then you can add a .env file in your project directory.
//String key = Dotenv.load().get("OPENAI_TOKEN");
openai = OpenAI.builder()
        .apiKey("API_KEY")
        .build();

messages = new ArrayList<>();
messages.add(ChatMessage.toSystemMessage("Help the user with their problem."));

// Here you can change the model's settings, add tools, and more.
request = ChatRequest.builder()
        .model("gpt-4o")
        .messages(messages)
        .build();

private byte[] downloadFile(String url) throws ClientProtocolException, IOException {
    HttpGet request = new HttpGet(url.replace(" ", "%20"));
    request.addHeader("sec-ch-ua",
        "\" Not A;Brand\";v=\"99\", \"Chromium\";v=\"130\", \"Microsoft Edge\";v=\"130\"");
    request.addHeader("X-Requested-With", "XMLHttpRequest");
    request.addHeader("sec-ch-ua-mobile", "?0");
    request.addHeader(
        "User-Agent",
        "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36 Edg/130.0.0.0");
    request.addHeader("sec-ch-ua-platform", "\"Windows\"");
    request.addHeader("Origin", url); // to be fixed
    request.addHeader("Sec-Fetch-Site", "same-origin");
    request.addHeader("Sec-Fetch-Mode", "cors");
    request.addHeader("Sec-Fetch-Dest", "empty");
    request.addHeader("Referer", url);
    request.addHeader("Accept-Language", "en-US,en;q=0.9");
    request.addHeader("sec-gpc", "1");
    DefaultHttpClient httpClient = new DefaultHttpClient();
    request.addHeader(
            "sec-ch-ua",
            "\" Not A;Brand\";v=\"99\", \"Chromium\";v=\"100\", \"Microsoft Edge\";v=\"100\"");
    request.addHeader("sec-ch-ua-mobile", "?0");
    request.addHeader(
            "User-Agent",
            "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4863.0 Safari/537.36 Edg/100.0.1163.1");
    CloseableHttpResponse response = httpClient.execute(request);
    InputStream is = response.getEntity().getContent();
    byte[] b = new byte[1024];
    int r;
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    while ((r = is.read(b)) != -1) {
        baos.write(Arrays.copyOf(b, r));
        baos.flush();
    }
    baos.close();
    return baos.toByteArray();
}

if (label.equalsIgnoreCase("chatgpt")) {
    if (args.length == 0) {
        sender.sendMessage('\r' + "Unknown translation key: command.unknown.argument");
        sender.sendMessage('\r' + label + " " + String.join(" ", args)
                + "Unknown translation key: command.context.here");
        return;
    } else if (args[0].equalsIgnoreCase("upload") && args.length >= 2) {
        String url = args[1];
        String fn = url.substring(url.lastIndexOf("/") + 1, url.length());
        System.out.println(fn);
        byte[] b = null;
        try {
            b = downloadFile(url);
        } catch (ClientProtocolException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        UploadFileRequest ufr = UploadFileRequest.builder().byteArray(fn, b).purpose(FilePurpose.ASSISTANTS).build();
        FileObject fo = openai.files().upload(ufr);
        System.out.println(fo);
        return;
    }
    String input = String.join(" ", args);
    messages.add(ChatMessage.toUserMessage(input));
    ChatResponse response = openai.createChatCompletion(request);
    sender.sendMessage('\r' + response.get(0).getMessage().getContent());
    messages.add(response.get(0).getMessage());
}

when running command chatgpt upload https://litter.catbox.moe/f4a2f1.jpg it results in this error

java.io.IOException: Unexpected code Response{protocol=http/1.1, code=415, message=Unsupported Media Type, url=https://api.openai.com/v1/files}, received: {
  "error": {
    "message": "Invalid Content-Type header (application/json; charset=utf-8), expected multipart/form-data. (HINT: If you're using curl, you can pass -H 'Content-Type: multipart/form-data')",
    "type": "invalid_request_error",
    "param": null,
    "code": null
  }
}

	at com.cjcrafter.openai.RequestHelper.executeRequest(RequestHelper.kt:66)
	at com.cjcrafter.openai.RequestHelper.executeRequest(RequestHelper.kt:77)
	at com.cjcrafter.openai.files.FileHandlerImpl.upload(FileHandlerImpl.kt:11)

and yes im fully aware im not doing my code right if i intend on actually using the uploaded file in the given chat thread to talk to gpt-4o, this is just a mere test of the file upload api for ChatGPT-Java-API which seems to be failing
Invalid Content-Type header (application/json; charset=utf-8), expected multipart/form-data. (HINT: If you're using curl, you can pass -H 'Content-Type: multipart/form-data') seems to be a error in ChatGPT-Java-API and not my code