File upload via PHP does not work, no error returned (localhost, XAMPP, ubuntu)

I'm following a Youtube tutorial

I plan to use this upload system later in conjunction with the basic system I'm creating for personal use.

I did exactly what I said in the tutorial except I was using the PDO * connection template.

By choosing the file and clicking send simply I go back to my page with no error, no files and nothing in the database.

Here is my code for review:

<?php

        include('database.php');

        // Create connection
        $conn = mysqli_connect($servername, $username, $password, $dbname);

        // Check connection
        if (!$conn) {
        die("Connection failed: " . mysqli_connect_error());
        }

        $msg = false;

        if(isset($_FILES['arquivo'])){
        $extensao = strtolower(substr($_FILES['arquivo']['name'], -4));
        $novo_nome = md5(time()).$extensao;
        $diretorio = "upload/";

        move_uploaded_file($_FILES['arquivo']['tmp_name'], $diretorio.$novo_nome);

        $sql = "INSERT INTO arquivo (codigo, arquivo, data) VALUES (null, '$novo_nome', NOW() )";

        if (mysqli_query($conn, $sql))
             $msg = "Arquivo upado com sucesso.";
            else 
             $msg = "Erro ao upar arquivo" . mysqli_error($conn);}


?>
<h1> Upload de Arquivos </h1>
<?php if($msg != false) echo "<p> $msg </p>"; ?>

<form action="upload.php" method="POST" enctype="multipart/form-data">
    <input type="file" required nome="arquivo"  />
    <input type="submit" value="Enviar" />
</form>

I put it in the pastebin because here I was going wrong, out of the block I'm not an expert around here

Does anyone know what's going on?

Screenshot

Thanks in advance for all your help