PHP Help Regisiter with image upload

I’m trying to integrate an image upload into the customer add area that will also be saved in the database with the name + uploaded to the folder, I managed to save it in the database but I can’t get it to upload. Can someone tell me what’s wrong? Thanks

Upload form

                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <form enctype="multipart/form-data" method="POST" action="test2.php">
                                        <label for="password">Carte Auto</label>
                                        <input type="file" id="file" name="file" required="true" placeholder="Carte Auto">
                                    </div>
                                </div>

Client add .php

<?php  
session_start();
error_reporting(0);
include('includes/dbconnection.php');
if (strlen($_SESSION['adid']==0)) {
  header('location:logout.php');
  } else{

?>

<?php 
session_start();
error_reporting(0);
include('includes/dbconnection.php');
if(isset($_POST['submit']))
  {
    $fname=$_POST['fullname'];
    $mobno=$_POST['mobilenumber'];
    $email=$_POST['email'];
    $password=md5($_POST['password']);
    $marca=$_POST['marca'];
    $model=$_POST['model'];
    $km=$_POST['km'];
    $servizio=$_POST['servicedate'];
    $carte=$_POST['file'];

    $ret=mysqli_query($con, "select Email from tbluser where Email='$email' || MobileNo='$mobno'");
    $result=mysqli_fetch_array($ret);
    if($result>0){
$msg="Questo indirizzo email o numero di contatto è già associato a un altro account";
    }
    else{
    $query=mysqli_query($con, "insert into tbluser(FullName, MobileNo, Email, Password, CarModel, CarMarca, CarKM, servizio, carte) value('$fname', '$mobno', '$email', '$password', '$marca', '$model', '$km', '$servizio', '$carte')");
    if ($query) {
    $msg="Il cliente si è registrato con successo";
  }
  else
    {
      $msg="Qualcosa è andato storto. Riprova.";
    }
}
}
 ?>
<!doctype html>
<html lang="en">

    <head>
        <meta charset="utf-8" />
        <title>ALL-IN GARAGE SERVICE</title>
        <!-- App css -->
        <link href="../assets/css/bootstrap.min.css" rel="stylesheet" type="text/css" />
        <link href="../assets/css/icons.css" rel="stylesheet" type="text/css" />
        <link href="../assets/css/metismenu.min.css" rel="stylesheet" type="text/css" />
        <link href="../assets/css/style.css" rel="stylesheet" type="text/css" />

        <script src="../assets/js/modernizr.min.js"></script>

    </head>


    <body>

        <!-- Begin page -->
        <div id="wrapper">

          <?php include_once('includes/sidebar.php');?>
            <div class="content-page">
                 <?php include_once('includes/header.php');?>
                <!-- Start Page content -->
                <div class="content">
                    <div class="container-fluid">

                        <div class="row">
                            <div class="col-12">
                                <div class="card-box">
                                    <h4 class="m-t-0 header-title">ALL-IN GARAGE | aggiungere un cliente</h4>
                                    <p class="text-muted m-b-30 font-14">
                                       
                                    </p>

                                </a>
                            </h3>
                              <hr color="#000" />
                                                <p style="font-size:16px; color:red" align="center"> <?php if($msg){
    echo $msg;
  }  ?> </p>

                            <form class="form-horizontal" action="" name="signup" method="post" onsubmit="return checkpass();">

                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="username">Nome</label>
                                        <input class="form-control" type="text" id="fullname"name="fullname" required="" placeholder="Inserisci il tuo nome completo">
                                    </div>
                                </div>

                                 <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="username">Telefono</label>
                                        <input class="form-control" type="text" id="mobilenumber" name="mobilenumber" required="" placeholder="Inserisci il tuo numero di cellulare" maxlength="15" pattern="[0-9]+">
                                    </div>
                                </div>
                                

                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="emailaddress">Auto Targa</label>
                                        <input class="form-control" type="text" id="email" name="email" required="" placeholder="Targa">
                                    </div>
                                </div>
                                
                                                                                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="password">Marca dell'auto </label>
                                        <input class="form-control" type="text required="" id="marca" name="marca" placeholder="Modello di auto">
                                    </div>
                                </div>


                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="password">Modello di auto</label>
                                        <input class="form-control" type="text" required="" id="model" name="model" placeholder="Marca dell'auto">
                                    </div>
                                </div>
                                
                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <label for="password">Scadenza revisione </label>
                                        <input class="form-control" type="date" required="" id="servicedate" name="servicedate" required="true" placeholder="Marca dell'auto">
                                    </div>
                                </div>
                                
                                <div class="form-group row m-b-20">
                                    <div class="col-12">
                                        <form enctype="multipart/form-data" method="POST" action="test2.php">
                                        <label for="password">Carte Auto</label>
                                        <input type="file" id="file" name="file" required="true" placeholder="Carte Auto">
                                    </div>
                                </div>
                                


                                <div class="form-group row text-center m-t-10">
                                    <div class="col-12">
                                        <button class="btn btn-block btn-custom waves-effect waves-light" type="submit" name="submit" >Aggiungi</button>
                                    </div>
                                </div>

                            </form>

                            <div class="row m-t-50">
                                <div class="col-sm-12 text-center">
                                </div>
                            </div>
   


</table>

                                                
                                            </div>
                                        </div>

                                    </div>
                                    <!-- end row -->

                                </div> <!-- end card-box -->
                            </div><!-- end col -->
                        </div>
                        <!-- end row -->
                    </div> <!-- container -->

                </div> <!-- content -->

             <?php include_once('includes/footer.php');?>
            </div>
        </div>
        <!-- jQuery  -->
        <script src="../assets/js/jquery.min.js"></script>
        <script src="../assets/js/bootstrap.bundle.min.js"></script>
        <script src="../assets/js/metisMenu.min.js"></script>
        <script src="../assets/js/waves.js"></script>
        <script src="../assets/js/jquery.slimscroll.js"></script>

        <!-- App js -->
        <script src="../assets/js/jquery.core.js"></script>
        <script src="../assets/js/jquery.app.js"></script>

    </body>
</html>
<?php }  ?>

test2.php ( upload php )

<?php
$allowedExts = array("gif", "jpeg", "jpg", "png");
$extension = end(explode(".", $_FILES["file"]["name"]));
if ((($_FILES["file"]["type"] == "image/gif")
|| ($_FILES["file"]["type"] == "image/jpeg")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/png"))
&& ($_FILES["file"]["size"] < 350000)
&& in_array($extension, $allowedExts))
  {
  if ($_FILES["file"]["error"] > 0)
    {
    echo "Return Code: " . $_FILES["file"]["error"] . "<br>";
    }
  else
    {
    echo "Upload: " . $_FILES["file"]["name"] . "<br>";
    echo "Type: " . $_FILES["file"]["type"] . "<br>";
    echo "Size: " . ($_FILES["file"]["size"] / 1024) . " kB<br>";
    echo "Temp file: " . $_FILES["file"]["tmp_name"] . "<br>";

    if (file_exists("uploads/" . $_FILES["file"]["name"]))
      {
      echo $_FILES["file"]["name"] . " already exists. ";
      }
    else
      {
      move_uploaded_file($_FILES["file"]["tmp_name"],
      "uploads/" . $_FILES["file"]["name"]);
      echo "Stored in: " . "uploads/" . $_FILES["file"]["name"];
      }
    }
  }
else
  {
  echo "Invalid file";
  }
?>

what is wrong there ? thanks