Cancellations - NodeJS - Mercado Pago Developers
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Create cancellation

It is possible to cancel a specific purchase from the payment ID using the SDK below. For details on request parameters, check the Cancellation API.

const client = new MercadoPago({ accessToken: 'ACCESS_TOKEN' });
const payments = new Payments(client);
payments.cancel('123456789', { idempotencyKey: '<SOME_UNIQUE_VALUE>' })
    .then((result) => { console.log(result); })
    .catch((error) => { console.error(error); });