add_filter( 'gform_product_info', function( $product_info, $form, $entry ) {
      // 6 is the qty field ID of the form you need to change it with your form qty id
    if ( rgar( $entry, 6 ) > 2 ) {
        $total = get_total($product_info);
        $fee = ($total * 0.6);
        $product_info = array(
            'products' => array(
                array(
                    'name'     => 'Discounted',
                    'price'    => $fee,
                    'quantity' => 1,
                ),
            ),
        );
    } else if ( rgar( $entry, 6 ) > 1 ) {
        $total = get_total($product_info);
        $fee2 = ($total * 0.7);
        $product_info = array(
            'products' => array(
                array(
                    'name'     => 'Discounted',
                    'price'    => $fee2,
                    'quantity' => 1,
                ),
            ),
        );
    }

    return $product_info;
}, 10, 3 );


function get_total($products) {
    $total = 0;
    foreach($products["products"] as $product){

        $price = GFCommon::to_number($product["price"]);
        if(isset($product["options"]) && is_array($product["options"])){
            foreach($product["options"] as $option){
                $price += GFCommon::to_number($option["price"]);
            }
        }
        $subtotal = floatval($product["quantity"]) * $price;
        $total += $subtotal;
    }
    $total += floatval($products["shipping"]["price"]);
    return $total;
}