BAD_REQUEST_ERROR:Account number is mandatory for this merchant

I'm trying to generate the orderId in Razorpay, and I'm following the steps given in documentation
https://razorpay.com/docs/payments/server-integration/java/payment-gateway/build-integration/#api-sample-code
. But its throwing an error saying com.razorpay.RazorpayException: BAD_REQUEST_ERROR:Account number is mandatory for this merchant

My code:
`RazorpayClient client = null;
try {
client = new RazorpayClient("[YOUR_KEY_ID]", "[YOUR_KEY_SECRET]");
JSONObject options = new JSONObject();
options.put("amount", 100);
options.put("currency", "INR");
options.put("receipt", "order_receipt_id");
Order order = client.orders.create(options);
System.out.println("ORDER Details: "+order);

        String orderId = order.get("id");  // Corrected property name to lowercase "id"
        System.out.println("ORDER ID: " + orderId);
        response.getWriter().append(orderId);
    }catch(Exception e){
        e.printStackTrace();
    }`

Note: I've added my key id and key secret in their respective "[YOUR_KEY_ID]", "[YOUR_KEY_SECRET]"

Then I tried adding

options.put("account_number", "[accNO]");
then it threw a different error saying Internal server error try after some time... and I've tried many times but still nothing.

and the Razorpay version I'm using is 1.4.3

Start with the linked Java payment-gateway documentation and the RazorpayClient.orders.create entry point shown in the issue. Reproduce the request using SDK version 1.4.3 and compare the behavior with and without account_number; done means the required merchant configuration or a reproducible SDK/API defect is clearly identified.