diff --git a/src/ValueObject/Request/OrderRequest.php b/src/ValueObject/Request/OrderRequest.php
index ff51273..de6e31a 100644
--- a/src/ValueObject/Request/OrderRequest.php
+++ b/src/ValueObject/Request/OrderRequest.php
@@ -27,7 +27,7 @@ public function __construct(
         public readonly string $currencyCode,
         public readonly int $totalAmount,
         public readonly string $customerIp,
-        public readonly string $notifyUrl,
+        public readonly ?string $notifyUrl = null,
         public readonly array $products = [],
         public readonly ?int $validityTime = null,
         public readonly ?string $extOrderId = null,