$client = new Client('api-key');
$client->useSandbox();
$client->banks->search(searchString);
$client->session->create(SessionResource);
$client->session->retrieve(id);
$client->merchant->update(MerchantResource);
$client->refund->single(RefundRequestResource);
$client->refund->batch(array<RefundRequestResource>);
$client->order->retrieve(id);
$client->order->update(OrderResource);
Docs: https://docs.getivy.de/