diff --git a/app/Http/Resources/RoomResource.php b/app/Http/Resources/RoomResource.php
index c2eab34..6dbdf5f 100644
--- a/app/Http/Resources/RoomResource.php
+++ b/app/Http/Resources/RoomResource.php
@@ -14,16 +14,14 @@ class RoomResource extends JsonResource
      */
     public function toArray(Request $request): array
     {
-        return [
-            'id'         => $this->id,
-            'branch_id'  => $this->branch_id,
-            'type'       => $this->type,
-            'name'       => $this->name,
-            'floor'      => $this->floor,
-            'is_online'  => $this->is_online,
-            'status'     => $this->status,
-            'started_at' => optional($this->started_at)->timezone('Asia/Taipei')->format('Y-m-d H:i:s'),
-            'ended_at'   => optional($this->ended_at)->timezone('Asia/Taipei')->format('Y-m-d H:i:s'),
-        ];
+        $array = parent::toArray($request);
+        $array['started_at'] = $this->formatTaipei($this->started_at);
+        $array['ended_at'] = $this->formatTaipei($this->ended_at);
+        return $array;
+    }
+
+    protected function formatTaipei(?Carbon $value): ?string
+    {
+        return $value ? $value->timezone('Asia/Taipei')->format('Y-m-d H:i:s') : null;
     }
 }