diff --git a/app/Services/NumberingService.php b/app/Services/NumberingService.php
index 6b68960b..69bf9be5 100644
--- a/app/Services/NumberingService.php
+++ b/app/Services/NumberingService.php
@@ -10,7 +10,7 @@ class NumberingService extends Service
     /**
      * 채번 규칙 기반 번호 생성
      *
-     * @param  string  $documentType  문서유형 (quote, order, sale, work_order, material_receipt)
+     * @param  string  $documentType  문서유형 (quote, order, sale, work_order, material_receipt, stock_production)
      * @param  array  $params  외부 파라미터 (pair_code, product_category 등)
      * @return string|null 생성된 번호 (규칙 없으면 null → 호출자가 기존 로직 사용)
      */
@@ -49,14 +49,14 @@ public function generate(string $documentType, array $params = []): ?string
                 case 'param':
                     $value = $params[$segment['key']] ?? $segment['default'] ?? '';
                     $result .= $value;
-                    $scopeKey = $value;
+                    $scopeKey .= $value;
                     break;
 
                 case 'mapping':
                     $inputValue = $params[$segment['key']] ?? '';
                     $value = $segment['map'][$inputValue] ?? $segment['default'] ?? '';
                     $result .= $value;
-                    $scopeKey = $value;
+                    $scopeKey .= $value;
                     break;
 
                 case 'sequence':
@@ -121,13 +121,13 @@ public function preview(string $documentType, array $params = []): ?array
                 case 'param':
                     $value = $params[$segment['key']] ?? $segment['default'] ?? '';
                     $result .= $value;
-                    $scopeKey = $value;
+                    $scopeKey .= $value;
                     break;
                 case 'mapping':
                     $inputValue = $params[$segment['key']] ?? '';
                     $value = $segment['map'][$inputValue] ?? $segment['default'] ?? '';
                     $result .= $value;
-                    $scopeKey = $value;
+                    $scopeKey .= $value;
                     break;
                 case 'sequence':
                     $periodKey = match ($rule->reset_period) {
@@ -188,4 +188,4 @@ private function nextSequence(
             ->where('period_key', $periodKey)
             ->value('last_sequence');
     }
-}
\ No newline at end of file
+}