Why is not the image updated in the database?

I have a problem about updating the image in my database, I do not know if the WHERE condition in the UPDATE (upload_banner.php) is badly formulated or I lack code, if you could help me solve it, it would be very helpful, thank you very much !!!

producto.php

$sql_last=mysqli_query($con,"select LAST_INSERT_ID(id_producto) as last from products order by id_producto desc limit 0,1");
    $rw=mysqli_fetch_array($sql_last);
    $id_producto=intval($rw['last']);
    $sql=mysqli_query($con,"select * from products where id_producto='$id_producto' limit 0,1");
    //$id_producto=isset($_GET['id_producto']);
    //$sql=mysqli_query($con,"select * from products where id_producto='$id_producto' limit 0,1");
    $count=mysqli_num_rows($sql);
    if ($count==0){
        //header("location: bannerlist.php");
        //exit;
    }
    $rw=mysqli_fetch_array($sql);
    $images=$rw['images'];

  <div align="center">

                    <h3><span class="glyphicon glyphicon-picture"></span> Imagen</h3>

                        <form class="form-vertical">

                            <div class="form-group">

                                <div class="col-sm-12">

                                  <div class="fileinput fileinput-new" data-provides="fileinput">
                                      <div class="fileinput-new thumbnail" style="max-width: 100%;" >
                                          <img class="img-rounded" src="imagenes/<?php echo $images;?>" /> 
                                      </div>
                                      <div class="fileinput-preview fileinput-exists thumbnail" style="max-width: 250px; max-height: 250px;"></div>
                                      <div>
                                        <span class="btn btn-primary btn-file"><span class="fileinput-new">Selecciona una imagen</span>
                                        <span class="fileinput-exists" onclick="upload_image();">Cambiar imagen</span><input type="file" name="fileToUpload" id="fileToUpload" required onchange="upload_image();"></span>
                                        <a href="#" class="btn btn-danger fileinput-exists" data-dismiss="fileinput">Cancelar</a>
                                      </div>
                                  </div>
                                    <div class="upload-msg"></div>
                                </div>
                            </div>   
                        </form>
                  </div> 

<script>
        function upload_image(){
            $(".upload-msg").text('Cargando...');
            var id_producto=$("#id_producto").val();
            var inputFileImage = document.getElementById("fileToUpload");
            var file = inputFileImage.files[0];
            var data = new FormData();
            data.append('fileToUpload',file);
            data.append('id_producto',id_producto);

            $.ajax({
                url: "ajax/upload_banner.php",        // Url to which the request is send
                type: "POST",             // Type of request to be send, called as method
                data: data,               // Data sent to server, a set of key/value pairs (i.e. form fields and values)
                contentType: false,       // The content type used when sending data to the server.
                cache: false,             // To unable request pages to be cached
                processData:false,        // To send DOMDocument or non processed data file it is set to false
                success: function(data)   // A function to be called if request succeeds
                {
                    $(".upload-msg").html(data);
                    window.setTimeout(function() {
                    $(".alert-dismissible").fadeTo(500, 0).slideUp(500, function(){
                    $(this).remove();
                    }); }, 5000);
                }
            }); 
        }

</script>

upload_banner.php

<?php
if($_SERVER['REQUEST_METHOD'] == "POST" && isset($_FILES["fileToUpload"]["type"])){
/* Llamar la Cadena de Conexion*/ 
include ("../config/db.php");
include ("../config/conexion.php");

$id_producto=intval($_POST['id_producto']);
$target_dir = "../imagenes/";
$carpeta=$target_dir;
if (!file_exists($carpeta)) {
    mkdir($carpeta, 0777, true);
}

$target_file = $carpeta . basename($_FILES["fileToUpload"]["name"]);
$uploadOk = 1;
$imageFileType = pathinfo($target_file,PATHINFO_EXTENSION);
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) {
    $check = getimagesize($_FILES["fileToUpload"]["tmp_name"]);
    if($check !== false) {
        $errors[]= "El archivo es una imagen - " . $check["mime"] . ".";
        $uploadOk = 1;
    } else {
        $errors[]= "El archivo no es una imagen.";
        $uploadOk = 0;
    }
}
// Check if file already exists
if (file_exists($target_file)) {
    $errors[]="Lo sentimos, la imagen ya existe.";
    $uploadOk = 0;
}
// Check file size
if ($_FILES["fileToUpload"]["size"] > 524288) {
    $errors[]= "Lo sentimos, el archivo es demasiado grande.  Tamaño máximo admitido: 0.5 MB";
    $uploadOk = 0;
}
// Allow certain file formats
if($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType != "jpeg"
&& $imageFileType != "gif" ) {
    $errors[]= "Lo sentimos, sólo archivos JPG, JPEG, PNG & GIF  son permitidos.";
    $uploadOk = 0;
}
// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0) {
    $errors[]= "Lo sentimos, tu imagen no fue insertada.";
// if everything is ok, try to upload file
} else {
    if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file)) {
       $messages[]= "La imagen se ha sido insertado correctamente.";
       $ruta=$_FILES["fileToUpload"]["name"];
       $update=mysqli_query($con,"UPDATE products SET images='$ruta' WHERE id_producto='$id_producto'");

    } else {
       $errors[]= "Lo sentimos, hubo un error subiendo la imagen.";
    }
}

if (isset($errors)){
    ?>
    <div class="alert alert-danger alert-dismissible" role="alert">
      <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
      <strong>Error!</strong> 
      <?php
      foreach ($errors as $error){
          echo"<p>$error</p>";
      }
      ?>
    </div>
    <?php
}

if (isset($messages)){
    ?>
    <div class="alert alert-success alert-dismissible" role="alert">
      <button type="button" class="close" data-dismiss="alert" aria-label="Close"><span aria-hidden="true">&times;</span></button>
      <strong>Aviso!</strong> 
      <?php
      foreach ($messages as $message){
          echo"<p>$message</p>";
      }
      ?>
    </div>
    <?php
}
}
?>