diff --git a/application/controllers/information.php b/application/controllers/information.php
index 6a02012b..a9231e06 100644
--- a/application/controllers/information.php
+++ b/application/controllers/information.php
@@ -989,7 +989,7 @@ class Information extends CI_Controller
       $recommand_information = $this->recommand_information($information);
       $tipsRightList = [];
       for ($i=0; $i < 36; $i++) { 
-        $key = 'List Tips Right '.i;
+        $key = 'List Tips Right '.$i;
         if (array_key_exists($key, $recommand_information)) {
           $tipsRightList[] = $recommand_information[$key];
         }