Payment Module

[Nanox Flow]

Hi!

Im developing one Payment gateway module, but im facing one issue I cant get the client currency

i have the file module.php on modules/gateway/ and on that file i have the Gateway Params and function module ($params)
On the function module($params) i have the postfield and $currency params, here the module get the currency well

The Postfields send to another page that are located on public_html/ gateway.php

The problem that im facing in on that file gateway.php on that fle I have

?php
use WHMCS\ClientArea;
use WHMCS\Database\Capsule;
use WHMCS\ModuleApi\ModuleApiCall as ModuleApiCall;
use WHMCS\ModuleApi\GatewayVars as GatewayVars;

define('CLIENTAREA', true);
$baseDir = realpath(__DIR__);
if (file_exists(__DIR__ . '/init.php')) {
    require_once __DIR__ . '/init.php';
}
if (file_exists(__DIR__ . '/includes/gatewayfunctions.php')) {
    require_once __DIR__ . '/includes/gatewayfunctions.php';
}
if (file_exists(__DIR__ . '/includes/invoicefunctions.php')) {
    require_once __DIR__ . '/includes/invoicefunctions.php';

global $whmcs;
global $_LANG;

On that file i want get the Client currency it, i have tried, but not sucess, on that file im able to get the $gatewayParams the paratemers fields of the Gateway

$currency = $whmcs->get_req_var('currency');
$clientcurrency = $params['clientdetails']['currency'];

Thanks