Friends dropdown help

Hello i have conversation plugin installed on elgg  1.7.8.

The autocomplete does no seem to work so i want to change it to dropdown. I was able to do it but i can't seem to get any friends to display in the dropdown menu. Below is my code

echo "To: " . elgg_view('input/dropdown', array('internalname' => 'receiver', 'internalid' => 'receiver', 'match_on' => 'friends'));

Please what is wrong?