Link not passing variables PHP

This is part of the script:

while($groupListRow = mysql_fetch_array($groupListResult))
$groupId = $groupListRow["id"];
$list = $groupListRow["groupName"];
echo("<li>" . $list . " - <a href='EDIT_group.php?id=$groupId&groupName=$list'>Edit</a></li>");

This is what comes out on the address bar after clicking the link:

This EDIT_group.php where it should go.

echo ($id);
echo ($groupName);

Why doesn’t it print? The variables show on the address bar! What am I doing wrong? :h: