curl --request POST \
  --url https://eu.sequencehq.com/api/credit-note-applications \
  --header 'Authorization: <authorization>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "creditNoteId": "af60cab3-812d-4250-a051-0fb7133a00c7",
  "invoiceId": "61b083e0-1faa-47ca-9aeb-6205da8f6c47",
  "amount": 50,
  "currency": "USD",
  "creditNoteBalanceVersion": 3,
  "invoiceBalanceVersion": 7
}
'

import requests

url = "https://eu.sequencehq.com/api/credit-note-applications"

payload = {
    "creditNoteId": "af60cab3-812d-4250-a051-0fb7133a00c7",
    "invoiceId": "61b083e0-1faa-47ca-9aeb-6205da8f6c47",
    "amount": 50,
    "currency": "USD",
    "creditNoteBalanceVersion": 3,
    "invoiceBalanceVersion": 7
}
headers = {
    "Authorization": "<authorization>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: '<authorization>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    creditNoteId: 'af60cab3-812d-4250-a051-0fb7133a00c7',
    invoiceId: '61b083e0-1faa-47ca-9aeb-6205da8f6c47',
    amount: 50,
    currency: 'USD',
    creditNoteBalanceVersion: 3,
    invoiceBalanceVersion: 7
  })
};

fetch('https://eu.sequencehq.com/api/credit-note-applications', 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://eu.sequencehq.com/api/credit-note-applications",
  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([
    'creditNoteId' => 'af60cab3-812d-4250-a051-0fb7133a00c7',
    'invoiceId' => '61b083e0-1faa-47ca-9aeb-6205da8f6c47',
    'amount' => 50,
    'currency' => 'USD',
    'creditNoteBalanceVersion' => 3,
    'invoiceBalanceVersion' => 7
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: <authorization>",
    "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://eu.sequencehq.com/api/credit-note-applications"

	payload := strings.NewReader("{\n  \"creditNoteId\": \"af60cab3-812d-4250-a051-0fb7133a00c7\",\n  \"invoiceId\": \"61b083e0-1faa-47ca-9aeb-6205da8f6c47\",\n  \"amount\": 50,\n  \"currency\": \"USD\",\n  \"creditNoteBalanceVersion\": 3,\n  \"invoiceBalanceVersion\": 7\n}")

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

	req.Header.Add("Authorization", "<authorization>")
	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://eu.sequencehq.com/api/credit-note-applications")
  .header("Authorization", "<authorization>")
  .header("Content-Type", "application/json")
  .body("{\n  \"creditNoteId\": \"af60cab3-812d-4250-a051-0fb7133a00c7\",\n  \"invoiceId\": \"61b083e0-1faa-47ca-9aeb-6205da8f6c47\",\n  \"amount\": 50,\n  \"currency\": \"USD\",\n  \"creditNoteBalanceVersion\": 3,\n  \"invoiceBalanceVersion\": 7\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://eu.sequencehq.com/api/credit-note-applications")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = '<authorization>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"creditNoteId\": \"af60cab3-812d-4250-a051-0fb7133a00c7\",\n  \"invoiceId\": \"61b083e0-1faa-47ca-9aeb-6205da8f6c47\",\n  \"amount\": 50,\n  \"currency\": \"USD\",\n  \"creditNoteBalanceVersion\": 3,\n  \"invoiceBalanceVersion\": 7\n}"

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

This response has no body data.

{
  "ledgerTransactionId": "0192c1b6-7f3a-7000-8000-000000000001",
  "creditNoteId": "af60cab3-812d-4250-a051-0fb7133a00c7",
  "invoiceId": "61b083e0-1faa-47ca-9aeb-6205da8f6c47",
  "amount": 50,
  "currency": "USD",
  "appliedAt": "2026-05-28T12:34:56Z",
  "invoiceBalance": {
    "value": 150,
    "currency": "USD",
    "version": 8
  },
  "creditNoteBalance": {
    "value": 50,
    "currency": "USD",
    "version": 4
  }
}

This response has no body data.

This response has no body data.

{
  "message": "Balance version mismatch. Re-read current versions and retry.",
  "currentInvoiceBalance": {
    "value": 150,
    "currency": "USD",
    "version": 8
  },
  "currentCreditNoteBalance": {
    "value": 50,
    "currency": "USD",
    "version": 4
  }
}

This response has no body data.