[Here's the code from where I am sending id](https://i.stack.imgur.com/hm6c7.png)

In this code I am getting ID by using `$_GET['id']`. At start the `$_GET['id']` fetches id and the first query of SQL works to fetch the data in input fields but soon as I press EDIT button to update the data than the data stays same in database. I used echo after `isset($_POST['edit_user'])` but there is nothing in $id.

```
<?php
session_start();
include("config.php");
//echo $id=$_SESSION['id'];
$id = isset($_GET['id']) ? $_GET['id'] : '';

$sql = "SELECT * FROM phone WHERE id='$id'";
$res = $conn->query($sql);
$row = $res->fetch_assoc();
echo $n = isset($row['name']) ? $row['name'] : '';
echo $phone = isset($row['contacts']) ? $row['contacts'] : '';

if (isset($_POST['edit_user'])) {
    $name = $_POST['fname'];
    $number = $_POST['num'];
    //var_dump($name);
    $sql = "UPDATE phone SET name='$name', contacts='$number' WHERE id='$id'";
    //var_dump($sql);

    //var_dump($res);
    if ($conn->query($sql) == TRUE) {
        echo "<script>alert('You have successfuly updated user') </script>";
        header("location:index.php");
    } else {
        echo "<script>alert('Failed to edit user') </script>";
    }
    $conn->close();
}

?>

<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>EDIT USER</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"></script>
</head>

<body>
    <div class="container">
        <div class="col-md-12">
            <div class="row">
                <div class="col-md-4"></div>
                <div class="col-md-4" jumbotron my-5>
                    <h4 class="text-center my-2">Edit User</h4>
                    <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
                        <label>Name</label>
                        <input type="text" name="fname" class="form-control" autocomplete="off" required value="<?php echo $n ?>">
                        <label>Number</label>
                        <input type="text" name="num" class="form-control" autocomplete="off" required value="<?php echo $phone ?>">
                        <input type="submit" name="edit_user" value="Edit User" class="edituser">
                    </form>
                </div>

            </div>
        </div>
    </div>

</body>

</html>

```