curl --location 'https://uat-accounts.payu.in/oauth/token' \
  --header 'Content-Type: application/x-www-form-urlencoded' \
  -d 'client_id={{client_id}}' \
  -d 'client_secret={{client_secret}}' \
  -d 'grant_type=client_credentials' \
  -d 'scope=create_payment_links update_payment_links read_payment_links'

import requests

url = "https://uat-accounts.payu.in/oauth/token"

payload = {
    "client_id":     "{{client_id}}",
    "client_secret": "{{client_secret}}",
    "grant_type":    "client_credentials",
    "scope":         "create_payment_links update_payment_links read_payment_links"
}

response = requests.post(url, data=payload)
token_data = response.json()
access_token = token_data["access_token"]
print(access_token)

const axios = require('axios');
const qs = require('querystring');

const response = await axios.post(
  'https://uat-accounts.payu.in/oauth/token',
  qs.stringify({
    client_id:     '{{client_id}}',
    client_secret: '{{client_secret}}',
    grant_type:    'client_credentials',
    scope:         'create_payment_links update_payment_links read_payment_links'
  }),
  { headers: { 'Content-Type': 'application/x-www-form-urlencoded' } }
);

const { access_token, expires_in } = response.data;
console.log(access_token);

<?php
$ch = curl_init('https://uat-accounts.payu.in/oauth/token');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_POST           => true,
    CURLOPT_POSTFIELDS     => http_build_query([
        'client_id'     => '{{client_id}}',
        'client_secret' => '{{client_secret}}',
        'grant_type'    => 'client_credentials',
        'scope'         => 'create_payment_links update_payment_links read_payment_links'
    ]),
    CURLOPT_HTTPHEADER     => ['Content-Type: application/x-www-form-urlencoded']
]);
$response = json_decode(curl_exec($ch), true);
curl_close($ch);
echo $response['access_token'];

using var client = new HttpClient();

var request = new HttpRequestMessage(
    HttpMethod.Post,
    "https://uat-accounts.payu.in/oauth/token"
);

request.Content = new FormUrlEncodedContent(new[]
{
    new KeyValuePair<string, string>("client_id", "{{client_id}}"),
    new KeyValuePair<string, string>("client_secret", "{{client_secret}}"),
    new KeyValuePair<string, string>("grant_type", "client_credentials"),
    new KeyValuePair<string, string>("scope", "create_payment_links update_payment_links read_payment_links")
});

var response = await client.SendAsync(request);
var responseBody = await response.Content.ReadAsStringAsync();

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;

HttpClient client = HttpClient.newHttpClient();

String formData =
    "client_id={{client_id}}" +
    "&client_secret={{client_secret}}" +
    "&grant_type=client_credentials" +
    "&scope=create_payment_links update_payment_links read_payment_links";

HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://uat-accounts.payu.in/oauth/token"))
    .header("Content-Type", "application/x-www-form-urlencoded")
    .POST(HttpRequest.BodyPublishers.ofString(formData))
    .build();

HttpResponse<String> response = client.send(
    request,
    HttpResponse.BodyHandlers.ofString()
);

System.out.println(response.body());

{
  "access_token": "827c9f81aa7b9de0f0b33238733fa34a9f914fd41407fcac8fc73258aac1830e",
  "token_type": "Bearer",
  "expires_in": 7199,
  "scope": "create_payment_links update_payment_links read_payment_links",
  "created_at": 1790341162
}

{
  "error": "invalid_client",
  "error_description": "Client authentication failed due to unknown client, no client authentication included, or unsupported authentication method."
}