diff --git a/app/Models/Activity.php b/app/Models/Activity.php
index 6c477c3..426dd5a 100644
--- a/app/Models/Activity.php
+++ b/app/Models/Activity.php
@@ -40,7 +40,7 @@ class Activity extends Model
         parent::boot();
 
         self::creating(function ($model) {
-            $model->code = 'ysd' . date('Ym') . mt_rand(11, 99);
+            $model->code = 'ysd' . date('Ym') . mt_rand(100, 999);
         });
     }