insert into mysql problem

$connect= mysql_connect("localhost","root") or die ("Sorry, Can not connect to database");

mysql_select_db("login") or die (mysql_error());

$user=$_POST['staff'];
echo $user;

$query="SELECT  * from users where username='$user' ";
$result=mysql_query($query,$connect) or die(mysql_error());
$row=mysql_fetch_array($result);

$uid=$row['userid'];
echo $uid;

$query="SELECT  * from opt where userid='$uid' ";
$result=mysql_query($query,$connect) or die(mysql_error());
$row=mysql_fetch_array($result);

if($row['confirm']==0)
{

$query = "INSERT INTO opt (confirm) values(1)";
echo 'The user selected options has confirmed';


}
?>

mysql_query($query);

mysql_query($query);

$user = mysql_real_escape_string($user);