html form input not uploading text to mysql database

Question

html form not inputting text inside mysqldatabase.

        <div id="form-div">
            <form method="post" id="form-space" action="manage_content.php">
                <h6 id="close-text">close</h6>
                <input type="text" name="webname" id="webname" placeholder="Title"
                required="required"/>
                <input type="text" name="url" id="addurl" placeholder="url" required="required"/>
                <input type="submit" name="submit" value="Add Link" id="addlink"/>
            </form>         
        </div>

manage_content.php

<?php
$serverName = "localhost";
$dBUsername = "root";
$dBPassword = "";
$dBName = "registration";
$conn = mysqli_connect($serverName, $dBUsername, $dBPassword, $dBName);
if (!$conn) {
    die("Connection fails: " . mysqli_connect_error());
}
if(isset($_POST["submit"])){
    $webname = $_POST["webname"];
    $url = $_POST["url"];
    $sql = "INSERT INTO post (webname, url) VALUES (?, ?)";
    $stmt = mysqli_stmt_init($conn);
    if (!mysqli_stmt_prepare($stmt, $sql)) {
        die(mysqli_error($conn));
    }
    mysqli_stmt_bind_param($stmt, "ss", $webname, $url);
    mysqli_stmt_execute($stmt);
}
?>

both the html file and the php is in the same directory but, it is not working. Can't figure out the problem.