PHP PayPal SDK new design - PHP PayPal SDK new design

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设计在沙盒模式下还不可用。

$sdkConfig = array(
    'mode' => 'live',
);
$cred = new OAuthTokenCredential("CLIENT ID", "SECRET", $sdkConfig);
$apiContext = new ApiContext($cred, 'Request' . time());
$apiContext->setConfig($sdkConfig);