diff --git a/app/Http/Controllers/Sales/DemoTenantController.php b/app/Http/Controllers/Sales/DemoTenantController.php
index 1922909e..59f138c7 100644
--- a/app/Http/Controllers/Sales/DemoTenantController.php
+++ b/app/Http/Controllers/Sales/DemoTenantController.php
@@ -163,7 +163,7 @@ public function store(Request $request)
             'company_name' => $request->input('company_name'),
             'tenant_type' => 'DEMO_TRIAL',
             'tenant_st_code' => 'trial',
-            'demo_expires_at' => now()->addDays($request->input('duration_days', 30)),
+            'demo_expires_at' => now()->addDays((int) $request->input('duration_days', 30)),
             'demo_source_partner_id' => $partner?->id,
             'options' => $options,
             'is_active' => true,
@@ -196,7 +196,7 @@ public function extend(Request $request, int $id)
             return $this->htmxError('이미 연장된 체험입니다. 연장은 1회만 가능합니다.');
         }
 
-        $days = $request->input('days', 14);
+        $days = (int) $request->input('days', 14);
         $opts['demo_extended'] = true;
         $opts['demo_extended_at'] = now()->toDateTimeString();
         $opts['demo_extended_days'] = $days;