diff --git a/composer.json b/composer.json
index f11b5239..7cd2cc9c 100644
--- a/composer.json
+++ b/composer.json
@@ -2,7 +2,7 @@
     "name": "buckaroo/sdk",
     "description": "Buckaroo payment SDK",
     "license": "MIT",
-    "version": "1.16.0",
+    "version": "1.17.0",
     "type": "library",
     "require": {
         "php": "^8.1",
diff --git a/src/Handlers/HMAC/Hmac.php b/src/Handlers/HMAC/Hmac.php
index 0ef34533..5b3befb6 100644
--- a/src/Handlers/HMAC/Hmac.php
+++ b/src/Handlers/HMAC/Hmac.php
@@ -50,7 +50,11 @@ public function base64Data($data = null)
         {
             if (is_array($data))
             {
-                $data = json_encode($data, JSON_UNESCAPED_UNICODE | JSON_PRESERVE_ZERO_FRACTION);
+                $data = mb_convert_encoding(
+                    json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE),
+                    'UTF-8',
+                    'auto'
+                );
             }
 
             $md5 = md5($data, true);
diff --git a/src/Models/Company.php b/src/Models/Company.php
index 9d803e32..b2118e12 100644
--- a/src/Models/Company.php
+++ b/src/Models/Company.php
@@ -25,5 +25,5 @@ class Company extends Person
     protected string $companyName;
     protected bool $vatApplicable;
     protected string $vatNumber;
-    protected string $chamberOfCommerce;
+    protected ?string $chamberOfCommerce;
 }