diff --git a/app/Services/ProductService.php b/app/Services/ProductService.php
index baeb004..100461c 100644
--- a/app/Services/ProductService.php
+++ b/app/Services/ProductService.php
@@ -14,13 +14,13 @@ class ProductService extends Service
     /**
      * 카테고리 트리 전체 조회 (parent_id = null 기준)
      */
-    public static function getCategory($request)
+    public function getCategory($request)
     {
         $parentId = $request->parentId ?? null;
         $group = $request->group ?? 'category';
 
         // 재귀적으로 트리 구성
-        $list = self::fetchCategoryTree($parentId, $group);
+        $list = $this->fetchCategoryTree($parentId, $group);
 
         return $list;
     }