diff --git a/core/components/minishop3/src/Controllers/Api/Manager/OrdersController.php b/core/components/minishop3/src/Controllers/Api/Manager/OrdersController.php
index 58cec930..3b1eb51c 100644
--- a/core/components/minishop3/src/Controllers/Api/Manager/OrdersController.php
+++ b/core/components/minishop3/src/Controllers/Api/Manager/OrdersController.php
@@ -644,7 +644,7 @@ public function create(array $params = []): array
             'comment', 'text_address'
         ];
         foreach ($addressFields as $field) {
-            if (isset($params[$field])) {
+            if (array_key_exists($field, $params)) {
                 $address->set($field, $params[$field]);
             }
         }
@@ -1146,7 +1146,7 @@ public function updateProduct(array $params = []): array
         $changes = [];
 
         foreach ($allowedFields as $field) {
-            if (isset($params[$field])) {
+            if (array_key_exists($field, $params)) {
                 $oldValue = $orderProduct->get($field);
                 $value = $params[$field];
 
@@ -1160,9 +1160,11 @@ public function updateProduct(array $params = []): array
                     $value = max(0, (float)$value);
                 }
 
-                // Handle options (JSON)
-                if ($field === 'options' && is_array($value)) {
-                    $value = json_encode($value, JSON_UNESCAPED_UNICODE);
+                // Handle options (JSON); null clears options (OrderView getOptionsForSave())
+                if ($field === 'options') {
+                    if (is_array($value)) {
+                        $value = json_encode($value, JSON_UNESCAPED_UNICODE);
+                    }
                 }
 
                 // Track changes for logging
diff --git a/core/components/minishop3/src/Services/Customer/CustomerAddressManager.php b/core/components/minishop3/src/Services/Customer/CustomerAddressManager.php
index e45d12c4..d9d5cb85 100644
--- a/core/components/minishop3/src/Services/Customer/CustomerAddressManager.php
+++ b/core/components/minishop3/src/Services/Customer/CustomerAddressManager.php
@@ -230,7 +230,12 @@ public function update(int $addressId, int $customerId, array $data): bool
         }
 
         // Regenerate hash if address changed
-        if (isset($data['city']) || isset($data['street']) || isset($data['building']) || isset($data['room'])) {
+        if (
+            array_key_exists('city', $data)
+            || array_key_exists('street', $data)
+            || array_key_exists('building', $data)
+            || array_key_exists('room', $data)
+        ) {
             $address->set('hash', $this->generateHash(array_merge($address->toArray(), $data)));
         }
 
diff --git a/core/components/minishop3/src/Services/ExtraFieldsService.php b/core/components/minishop3/src/Services/ExtraFieldsService.php
index 01997fae..65c1f0b9 100644
--- a/core/components/minishop3/src/Services/ExtraFieldsService.php
+++ b/core/components/minishop3/src/Services/ExtraFieldsService.php
@@ -297,7 +297,7 @@ public function updateField(int $id, array $data): array
         $allowedFields = ['label', 'description', 'xtype', 'active', 'select_options'];
 
         foreach ($allowedFields as $fieldName) {
-            if (isset($data[$fieldName])) {
+            if (array_key_exists($fieldName, $data)) {
                 $field->set($fieldName, $data[$fieldName]);
             }
         }