if (isset($_POST['submit'])) {
    $username = $conn->real_escape_string($_POST['username']);
    $email = $conn->real_escape_string($_POST['email']);
    $password = password_hash($_POST['password'], PASSWORD_BCRYPT); // hashing the password

    // Corrected query
    $sql = "INSERT INTO users (username, email, password) VALUES ('$username', '$email', '$password')";

    if ($conn->query($sql) === TRUE) {
        echo "Registration successful";
    } else {
        echo "Error: " . $sql . "<br>" . $conn->error;
    }

    // Close the connection
    $conn->close();
}