diff --git a/Admin/Install/Application/Shop/Application.php b/Admin/Install/Application/Shop/Application.php
index 5d096d2..1621687 100755
--- a/Admin/Install/Application/Shop/Application.php
+++ b/Admin/Install/Application/Shop/Application.php
@@ -127,7 +127,7 @@ final class Application
 
         /* CSRF token OK? */
         if ($request->hasData('CSRF')
-            && !\hash_equals($this->app->sessionManager->get('CSRF'), $request->getDataString('CSRF'))
+            && !\hash_equals($this->app->sessionManager->data['CSRF'] ?? '', $request->getDataString('CSRF'))
         ) {
             $response->header->status = RequestStatusCode::R_403;
 
@@ -153,20 +153,20 @@ final class Application
 
         if ($account->id > 0) {
             $response->header->l11n = $account->l11n;
-        } elseif ($this->app->sessionManager->get('language') !== null
-            && $response->header->l11n->language !== $this->app->sessionManager->get('language')
+        } elseif (isset($this->app->sessionManager->data['language'])
+            && $response->header->l11n->language !== $this->app->sessionManager->data['language']
         ) {
             $response->header->l11n
                 ->loadFromLanguage(
-                    $this->app->sessionManager->get('language'),
-                    $this->app->sessionManager->get('country') ?? '*'
+                    $this->app->sessionManager->data['language'],
+                    $this->app->sessionManager->data['country'] ?? '*'
                 );
         } else {
             $this->app->setResponseLanguage($request, $response, $this->config);
         }
 
         if (!\in_array($response->header->l11n->language, $this->config['language'])) {
-            $response->header->l11n->setLanguage($this->app->l11nServer->language);
+            $response->header->l11n->language = $this->app->l11nServer->language;
         }
 
         $pageView = new ShopView($this->app->l11nManager, $request, $response);
diff --git a/Controller/ApiController.php b/Controller/ApiController.php
index c8d4511..3795abc 100755
--- a/Controller/ApiController.php
+++ b/Controller/ApiController.php
@@ -55,6 +55,7 @@ final class ApiController extends Controller
     public function apiItemFileDownload(RequestAbstract $request, ResponseAbstract $response, mixed $data = null) : void
     {
         // Handle public files
+        /** @var \Modules\ItemManagement\Models\Item $item */
         $item = ItemMapper::get()
             ->with('files')
             ->with('files/types')
@@ -76,11 +77,13 @@ final class ApiController extends Controller
 
         // Handle private files
         // @todo: this is another example where it would be useful to have clients and items as models in the bill and bill element
+        /** @var \Modules\ClientManagement\Models\Client $client */
         $client = ClientMapper::get()
             ->where('account', $request->header->account)
             ->execute();
 
         // @todo: only for sales invoice, currently also for offers
+        /** @var \Modules\Billing\Models\Bill[] $bills */
         $bills = BillMapper::getAll()
             ->with('elements')
             ->where('client', $client->id)
@@ -93,6 +96,7 @@ final class ApiController extends Controller
             $elements = $bill->getElements();
 
             foreach ($elements as $element) {
+                /** @var \Modules\ItemManagement\Models\Item $item */
                 $item = ItemMapper::get()
                     ->with('files')
                     ->with('files/type')