贝宝购买详情页面与空字段

I have a standard Paypal button like this:

    <!-- Identify your business so that you can collect the payments. -->
    <input type="hidden" name="business" value="info@mywebsite.com">

    <!-- Specify a Buy Now button. -->
    <input type="hidden" name="cmd" value="_xclick">

    <!-- Specify details about the item that buyers will purchase. -->
    <input type="hidden" name="item_name_1" value="My item Name 1">
    <input type="hidden" name="amount_1" value="1000">
    <input type="hidden" name="quantity_1" value="1">

    <input type="hidden" name="item_name_2" value="My item Name 2">
    <input type="hidden" name="amount_2" value="20">
    <input type="hidden" name="quantity_2" value="1">

    <input type="hidden" name="currency_code" value="EUR">

    <input type="hidden" name="notify_url" value="http://www.mywebsite.com/ipn-settings">
    <input type="hidden" name="return" value="http://www.mywebsite.com/DEV/grazie/">

    <input type="hidden" name="custom" value="24">
    <!-- Display the payment button. -->
    <input type="image" src="https://www.paypalobjects.com/it_IT/IT/i/btn/btn_buynowCC_LG.gif" border="0" name="submit" alt="PayPal è il metodo rapido e sicuro per pagare e farsi pagare online.">
    <img alt="" border="0" src="https://www.paypalobjects.com/it_IT/i/scr/pixel.gif" width="1" height="1">

</form>

On click it redirects me to the PayPal page but the description and the price field are empty. Only the quantity is set to 1 and is readonly. Is there something wrong with this button?

Thanks in advance for your help.

I had to change the cmd value to "_cart" and add the hidden input "upload" with value = 1

Now it works fine!