PHP PayPal SDK新设计

当我尝试使用PayPal结账时，我仍然收到旧的设计。如何切换到新的

$sdkConfig = array(
    'mode' => 'sandbox',
);

$cred = new OAuthTokenCredential("CLIENT ID", "SECRET", $sdkConfig);

$apiContext = new ApiContext($cred, 'Request' . time());
$apiContext->setConfig($sdkConfig);

---

新的PayPal设计尚未在沙箱模式下提供

$sdkConfig = array(
    'mode' => 'live',
);

$cred = new OAuthTokenCredential("CLIENT ID", "SECRET", $sdkConfig);

$apiContext = new ApiContext($cred, 'Request' . time());
$apiContext->setConfig($sdkConfig);