public function cancel_payment($id) {
        $request = array(
            "uri" => "/v1/payments/{$id}",
            "params" => array(
                "access_token" => $this->get_access_token()
            ),
            "data" => array(
                "status" => "cancelled"
            )
        );

        $response = MPRestClient::put($request);
        return $response;
    }