update number in sql pdo php not working

<?php
include("php-includes/check-login1.php"); 

echo $username;
$profile = "0"; 
require_once("config/pdo.php");	  
$data = [
    'profile' => $profile,
    'username' => $username,
   
];
$sql = "UPDATE customer SET photoup=:profile WHERE mmob=:username";
$stmt= $conn->prepare($sql);
$stmt->execute($data);
    if($stmt){
							echo "success";
							//echo '<script>window.location.assign("memhome.php");</script>';
							}


else
{
echo "error";
}


?>