curl --request DELETE \
  --url https://clob.polymarket.com/order \
  --header 'Content-Type: application/json' \
  --header 'POLY_ADDRESS: <api-key>' \
  --header 'POLY_API_KEY: <api-key>' \
  --header 'POLY_PASSPHRASE: <api-key>' \
  --header 'POLY_SIGNATURE: <api-key>' \
  --header 'POLY_TIMESTAMP: <api-key>' \
  --data '
{
  "orderID": "0xabcdef1234567890abcdef1234567890abcdef12"
}
'

import requests

url = "https://clob.polymarket.com/order"

payload = { "orderID": "0xabcdef1234567890abcdef1234567890abcdef12" }
headers = {
    "POLY_API_KEY": "<api-key>",
    "POLY_ADDRESS": "<api-key>",
    "POLY_SIGNATURE": "<api-key>",
    "POLY_PASSPHRASE": "<api-key>",
    "POLY_TIMESTAMP": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'DELETE',
  headers: {
    POLY_API_KEY: '<api-key>',
    POLY_ADDRESS: '<api-key>',
    POLY_SIGNATURE: '<api-key>',
    POLY_PASSPHRASE: '<api-key>',
    POLY_TIMESTAMP: '<api-key>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({orderID: '0xabcdef1234567890abcdef1234567890abcdef12'})
};

fetch('https://clob.polymarket.com/order', 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://clob.polymarket.com/order",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "DELETE",
  CURLOPT_POSTFIELDS => json_encode([
    'orderID' => '0xabcdef1234567890abcdef1234567890abcdef12'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "POLY_ADDRESS: <api-key>",
    "POLY_API_KEY: <api-key>",
    "POLY_PASSPHRASE: <api-key>",
    "POLY_SIGNATURE: <api-key>",
    "POLY_TIMESTAMP: <api-key>"
  ],
]);

$response = curl_exec($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://clob.polymarket.com/order"

	payload := strings.NewReader("{\n  \"orderID\": \"0xabcdef1234567890abcdef1234567890abcdef12\"\n}")

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

	req.Header.Add("POLY_API_KEY", "<api-key>")
	req.Header.Add("POLY_ADDRESS", "<api-key>")
	req.Header.Add("POLY_SIGNATURE", "<api-key>")
	req.Header.Add("POLY_PASSPHRASE", "<api-key>")
	req.Header.Add("POLY_TIMESTAMP", "<api-key>")
	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.delete("https://clob.polymarket.com/order")
  .header("POLY_API_KEY", "<api-key>")
  .header("POLY_ADDRESS", "<api-key>")
  .header("POLY_SIGNATURE", "<api-key>")
  .header("POLY_PASSPHRASE", "<api-key>")
  .header("POLY_TIMESTAMP", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"orderID\": \"0xabcdef1234567890abcdef1234567890abcdef12\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://clob.polymarket.com/order")

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

request = Net::HTTP::Delete.new(url)
request["POLY_API_KEY"] = '<api-key>'
request["POLY_ADDRESS"] = '<api-key>'
request["POLY_SIGNATURE"] = '<api-key>'
request["POLY_PASSPHRASE"] = '<api-key>'
request["POLY_TIMESTAMP"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"orderID\": \"0xabcdef1234567890abcdef1234567890abcdef12\"\n}"

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