curl --request POST \
  --url https://api.example.com/RedeemGiftCard \
  --header 'Content-Type: application/json' \
  --data '
{
  "MerchantGUID": "abcdabcd-abcd-abcd-abcd-abcdabcdabcd",
  "ShippingCountryCode": "UA",
  "Cards": [
    {
      "CardId": 167,
      "BalanceInGiftCardCurrency": 10,
      "BalanceInCustomerCurrency": 21.39,
      "GiftCardCurrencyCode": "GBP",
      "CustomerCurrencyCode": "EUR",
      "BalanceUsedInCardCurrency": 10,
      "BalanceUsedInCustomerCurrency": 21.39,
      "CardFields": {
        "CardId": "card10",
        "CardPin": "111"
      }
    }
  ]
}
'

import requests

url = "https://api.example.com/RedeemGiftCard"

payload = {
    "MerchantGUID": "abcdabcd-abcd-abcd-abcd-abcdabcdabcd",
    "ShippingCountryCode": "UA",
    "Cards": [
        {
            "CardId": 167,
            "BalanceInGiftCardCurrency": 10,
            "BalanceInCustomerCurrency": 21.39,
            "GiftCardCurrencyCode": "GBP",
            "CustomerCurrencyCode": "EUR",
            "BalanceUsedInCardCurrency": 10,
            "BalanceUsedInCustomerCurrency": 21.39,
            "CardFields": {
                "CardId": "card10",
                "CardPin": "111"
            }
        }
    ]
}
headers = {"Content-Type": "application/json"}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    MerchantGUID: 'abcdabcd-abcd-abcd-abcd-abcdabcdabcd',
    ShippingCountryCode: 'UA',
    Cards: [
      {
        CardId: 167,
        BalanceInGiftCardCurrency: 10,
        BalanceInCustomerCurrency: 21.39,
        GiftCardCurrencyCode: 'GBP',
        CustomerCurrencyCode: 'EUR',
        BalanceUsedInCardCurrency: 10,
        BalanceUsedInCustomerCurrency: 21.39,
        CardFields: {CardId: 'card10', CardPin: '111'}
      }
    ]
  })
};

fetch('https://api.example.com/RedeemGiftCard', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.example.com/RedeemGiftCard",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'MerchantGUID' => 'abcdabcd-abcd-abcd-abcd-abcdabcdabcd',
    'ShippingCountryCode' => 'UA',
    'Cards' => [
        [
                'CardId' => 167,
                'BalanceInGiftCardCurrency' => 10,
                'BalanceInCustomerCurrency' => 21.39,
                'GiftCardCurrencyCode' => 'GBP',
                'CustomerCurrencyCode' => 'EUR',
                'BalanceUsedInCardCurrency' => 10,
                'BalanceUsedInCustomerCurrency' => 21.39,
                'CardFields' => [
                                'CardId' => 'card10',
                                'CardPin' => '111'
                ]
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.example.com/RedeemGiftCard"

	payload := strings.NewReader("{\n  \"MerchantGUID\": \"abcdabcd-abcd-abcd-abcd-abcdabcdabcd\",\n  \"ShippingCountryCode\": \"UA\",\n  \"Cards\": [\n    {\n      \"CardId\": 167,\n      \"BalanceInGiftCardCurrency\": 10,\n      \"BalanceInCustomerCurrency\": 21.39,\n      \"GiftCardCurrencyCode\": \"GBP\",\n      \"CustomerCurrencyCode\": \"EUR\",\n      \"BalanceUsedInCardCurrency\": 10,\n      \"BalanceUsedInCustomerCurrency\": 21.39,\n      \"CardFields\": {\n        \"CardId\": \"card10\",\n        \"CardPin\": \"111\"\n      }\n    }\n  ]\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.example.com/RedeemGiftCard")
  .header("Content-Type", "application/json")
  .body("{\n  \"MerchantGUID\": \"abcdabcd-abcd-abcd-abcd-abcdabcdabcd\",\n  \"ShippingCountryCode\": \"UA\",\n  \"Cards\": [\n    {\n      \"CardId\": 167,\n      \"BalanceInGiftCardCurrency\": 10,\n      \"BalanceInCustomerCurrency\": 21.39,\n      \"GiftCardCurrencyCode\": \"GBP\",\n      \"CustomerCurrencyCode\": \"EUR\",\n      \"BalanceUsedInCardCurrency\": 10,\n      \"BalanceUsedInCustomerCurrency\": 21.39,\n      \"CardFields\": {\n        \"CardId\": \"card10\",\n        \"CardPin\": \"111\"\n      }\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.example.com/RedeemGiftCard")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"MerchantGUID\": \"abcdabcd-abcd-abcd-abcd-abcdabcdabcd\",\n  \"ShippingCountryCode\": \"UA\",\n  \"Cards\": [\n    {\n      \"CardId\": 167,\n      \"BalanceInGiftCardCurrency\": 10,\n      \"BalanceInCustomerCurrency\": 21.39,\n      \"GiftCardCurrencyCode\": \"GBP\",\n      \"CustomerCurrencyCode\": \"EUR\",\n      \"BalanceUsedInCardCurrency\": 10,\n      \"BalanceUsedInCustomerCurrency\": 21.39,\n      \"CardFields\": {\n        \"CardId\": \"card10\",\n        \"CardPin\": \"111\"\n      }\n    }\n  ]\n}"

response = http.request(request)
puts response.read_body

{
  "Cards": [
    {
      "CardId": 167,
      "BalanceInGiftCardCurrency": 10,
      "BalanceInCustomerCurrency": 21.39,
      "GiftCardCurrencyCode": "GBP",
      "CustomerCurrencyCode": "EUR",
      "BalanceUsedInCardCurrency": 10,
      "BalanceUsedInCustomerCurrency": 21.39,
      "RedeemTransactionId": "120423",
      "CardFields": {
        "CardId": "card10",
        "CardPin": "111"
      }
    }
  ]
}