diff --git a/blocks/online_users/block_online_users.php b/blocks/online_users/block_online_users.php
index fc019867bb4..a6c64071a01 100644
--- a/blocks/online_users/block_online_users.php
+++ b/blocks/online_users/block_online_users.php
@@ -73,7 +73,7 @@ class block_online_users extends block_base {
                       $courseselect
                       $timeselect
                       $groupselect
-                GROUP BY u.id 
+                GROUP BY u.id, u.username, u.firstname, u.lastname, u.picture, u.lastaccess, ul.timeaccess
                 ORDER BY ul.timeaccess DESC";