curl -X DELETE https://api2.ecomailapp.cz/tracker/transaction/transaction_1234/delete \
  -H "key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "transaction_data": {
      "shop": "someshop.com"
    }
  }'

$orderId = 'transaction_1234';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "https://api2.ecomailapp.cz/tracker/transaction/{$orderId}/delete");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'DELETE');
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'key: YOUR_API_KEY',
    'Content-Type: application/json',
]);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
    'transaction_data' => [
        'shop' => 'someshop.com',
    ],
]));
$response = curl_exec($ch);
curl_close($ch);

{
  "deleted": true
}