diff --git a/src/Payments/Standard/PendingPayment.php b/src/Payments/Standard/PendingPayment.php
index 5afe1d4..4dbf6fc 100644
--- a/src/Payments/Standard/PendingPayment.php
+++ b/src/Payments/Standard/PendingPayment.php
@@ -70,12 +70,12 @@ public static function fromArray(array $data): self
         if (isset($data['event']) && str_contains((string) $data['event'], 'checkout.session:created')) {
             return new self(
                 event: $data['event'],
-                checkoutUrl: $data['checkout_url'] ?? null,
                 reference: $data['data']['tx_ref'] ?? '',
                 currency: Currency::from($data['data']['currency'] ?? 'MWK'),
                 amount: (int) ($data['data']['amount'] ?? 0),
                 mode: $data['data']['mode'] ?? 'sandbox',
                 status: $data['data']['status'] ?? 'pending',
+                checkoutUrl: $data['checkout_url'] ?? null,
             );
         }
 
@@ -100,7 +100,7 @@ public static function fromArray(array $data): self
                     email: $data['customer']['email'] ?? null
                 ),
                 customization: empty($data['customization']) ? null : Customization::fromArray($data['customization']),
-                logs: empty($data['logs']) ? null : array_map(fn ($log): Log => Log::fromArray($log), $data['logs']),
+                logs: empty($data['logs']) ? null : array_map(Log::fromArray(...), $data['logs']),
                 createdAt: $data['created_at'] ?? null,
                 updatedAt: $data['updated_at'] ?? null,
             );
diff --git a/src/Payments/Standard/StandardOrder.php b/src/Payments/Standard/StandardOrder.php
index fd3dd65..5844987 100644
--- a/src/Payments/Standard/StandardOrder.php
+++ b/src/Payments/Standard/StandardOrder.php
@@ -52,8 +52,10 @@ public function toArray(): array
             'tx_ref' => $this->reference,
             'callback_url' => $this->callbackUrl,
             'return_url' => $this->returnUrl,
-            'title' => $this->title ?? null,
-            'description' => $this->description ?? null,
+            'customization' => [
+                'title' => $this->title ?? null,
+                'description' => $this->description ?? null,
+            ],
             'customer' => $this->customer?->toArray() ?? null,
             'meta' => $this->meta ?? null,
             'uuid' => $this->uuid ?? null,
diff --git a/src/Payments/Standard/StandardPayment.php b/src/Payments/Standard/StandardPayment.php
index c1f8b10..f71fed5 100644
--- a/src/Payments/Standard/StandardPayment.php
+++ b/src/Payments/Standard/StandardPayment.php
@@ -87,7 +87,6 @@ public function verify(Payment|string $payment): bool
     {
         $reference = $payment instanceof Payment ? $payment->reference() : $payment;
 
-        /** @var PendingPayment $payment */
         $payment = $this->retrieve($reference);
 
         return $payment->status === 'success';
diff --git a/src/Payments/Standard/ValueObjects/Authorization.php b/src/Payments/Standard/ValueObjects/Authorization.php
index 8ec6040..8ca0153 100644
--- a/src/Payments/Standard/ValueObjects/Authorization.php
+++ b/src/Payments/Standard/ValueObjects/Authorization.php
@@ -18,13 +18,13 @@
      * @param  ?string  $completedAt  The completed at date of the authorization.
      */
     public function __construct(
-        public readonly ?string $channel,
-        public readonly ?string $cardNumber,
-        public readonly ?string $expiry,
-        public readonly ?string $brand,
-        public readonly ?string $provider,
-        public readonly ?string $mobileNumber,
-        public readonly ?string $completedAt,
+        public ?string $channel,
+        public ?string $cardNumber,
+        public ?string $expiry,
+        public ?string $brand,
+        public ?string $provider,
+        public ?string $mobileNumber,
+        public ?string $completedAt,
     ) {
         //
     }
diff --git a/src/Payments/Standard/ValueObjects/Customization.php b/src/Payments/Standard/ValueObjects/Customization.php
index 0031d7d..4b741f7 100644
--- a/src/Payments/Standard/ValueObjects/Customization.php
+++ b/src/Payments/Standard/ValueObjects/Customization.php
@@ -14,9 +14,9 @@
      * @param  ?string  $logo  The logo of the customization.
      */
     public function __construct(
-        public readonly ?string $title,
-        public readonly ?string $description,
-        public readonly ?string $logo,
+        public ?string $title,
+        public ?string $description,
+        public ?string $logo,
     ) {
         //
     }
diff --git a/src/Payments/Standard/ValueObjects/Log.php b/src/Payments/Standard/ValueObjects/Log.php
index b1eafa5..c0a28dd 100644
--- a/src/Payments/Standard/ValueObjects/Log.php
+++ b/src/Payments/Standard/ValueObjects/Log.php
@@ -14,9 +14,9 @@
      * @param  string  $createdAt  The created at date of the log.
      */
     public function __construct(
-        public readonly string $type,
-        public readonly string $message,
-        public readonly string $createdAt,
+        public string $type,
+        public string $message,
+        public string $createdAt,
     ) {
         //
     }
diff --git a/src/Support/Reference.php b/src/Support/Reference.php
index 1348b0d..ad0e113 100644
--- a/src/Support/Reference.php
+++ b/src/Support/Reference.php
@@ -13,7 +13,7 @@
     /**
      * The prefix of the reference.
      */
-    public readonly string $ref;
+    public string $ref;
 
     /**
      * Creates a new reference instance.
diff --git a/src/Support/Webhook.php b/src/Support/Webhook.php
index cf4925a..a6f346f 100644
--- a/src/Support/Webhook.php
+++ b/src/Support/Webhook.php
@@ -70,8 +70,8 @@ public static function getCurrentRequest(): RequestInterface
 
         $headers = [];
         foreach ($_SERVER as $key => $value) {
-            if (str_starts_with($key, 'HTTP_')) {
-                $header = str_replace(' ', '-', ucwords(mb_strtolower(str_replace('_', ' ', mb_substr($key, 5)))));
+            if (str_starts_with((string) $key, 'HTTP_')) {
+                $header = str_replace(' ', '-', ucwords(mb_strtolower(str_replace('_', ' ', mb_substr((string) $key, 5)))));
                 $headers[$header] = [$value];
             }
 
diff --git a/tests/Payments/Standard/StandardOrderTest.php b/tests/Payments/Standard/StandardOrderTest.php
index 23c185f..70af11b 100644
--- a/tests/Payments/Standard/StandardOrderTest.php
+++ b/tests/Payments/Standard/StandardOrderTest.php
@@ -16,9 +16,6 @@
         returnUrl: 'https://example.com/return',
         title: 'Test Order',
         description: 'Test Order Description',
-        customer: null,
-        meta: null,
-        uuid: null,
     );
 
     // Assert
@@ -45,9 +42,6 @@
         returnUrl: 'https://example.com/return',
         title: 'Test Order',
         description: 'Test Order Description',
-        customer: null,
-        meta: null,
-        uuid: null,
     );
 
     // Assert
@@ -57,8 +51,10 @@
         'tx_ref' => '1234567890',
         'callback_url' => 'https://example.com/callback',
         'return_url' => 'https://example.com/return',
-        'title' => 'Test Order',
-        'description' => 'Test Order Description',
+        'customization' => [
+            'title' => 'Test Order',
+            'description' => 'Test Order Description',
+        ],
         'customer' => null,
         'meta' => null,
         'uuid' => null,