Magento 2 Apply Custom Discount to the Quote Programmatically

Question

I want to add custom discount to the quote programmatically but the total not updated and when place the order the discount is not affected.

$cartId = 199;    
$quote = $this->cartRepositoryInterface->get($cartId); // load empty cart quote
    $discount = 10; // in percent
    $quoteSubTotal = $quote->getSubtotal();
    $quoteBaseSubTotal = $quote->getBaseSubtotal();
        foreach ($quote->getAllVisibleItems() as $item) {
            $quoteItem = $quote->getItemById($item->getId());
            if($discount != 0) {
              $discountAmount = (float) (($quoteItem->getPrice()*$quoteItem->getQty())*$discount)/100;
            }
            $finalDiscount += $discountAmount;
            $item->setDiscountAmount($discountAmount);
            $item->setBaseDiscountAmount($discountAmount);
            $item->getProduct()->setIsSuperMode(true);
            $item->calcRowTotal();
            $item->save();
        }
        if($finalDiscount > 0) {
          $quote->setSubtotalWithDiscount($quoteSubTotal - $finalDiscount);
          $quote->setBaseSubtotalWithDiscount($quoteBaseSubTotal - $finalDiscount);
          $quote->setGrandTotal($quoteSubTotal - $finalDiscount);
          $quote->setBaseGrandTotal($quoteBaseSubTotal - $finalDiscount);
          $quote->collectTotals();
          $quote->collectTotals()->save();
        }

But It's not Working, Any suggestion please?