Magento percentage discount coupon codes not working after moving servers

Any of those help Here is my code which create the coupon code on the fly:

require_once('app/Mage.php');
Mage::app('default');
function generateUniqueId($length = null)
{
    $rndId = crypt(uniqid(rand(),1));
    $rndId = strip_tags(stripslashes($rndId));
    $rndId = str_replace(array(".", "$"),"",$rndId);
    $rndId = strrev(str_replace("/","",$rndId));
        if (!is_null($rndId)){
        return strtoupper(substr($rndId, 0, $length));
        }
    return strtoupper($rndId);
}
/* create unique coupon code */
for($cc = 0 ; $cc<15 ; $cc++){
    $productId  = 297;//(int) $this->getRequest()->getParam('id'); 
    $discountprice= 1;//$_POST['product']['discountprice']; 
    $model = Mage::getModel('salesrule/rule');
    $couponCode=generateUniqueId(8);
    $model->setName($couponCode);
    $model->setDescription('Discount coupon for Surger.');
    $model->setUsesPerCoupon(1);
    $model->setUsesPerCustomer(1);
    $model->setCustomerGroupIds('0,1');
    $model->setIsActive(1);
   // $model->setConditionsSerialized('a:6:{s:4:\"type\";s:32:\"salesrule/rule_condition_combine\";s:9:\"attribute\";N;s:8:\"operator\";N;s:5:\"value\";s:1:\"1\";s:18:\"is_value_processed\";N;s:10:\"aggregator\";s:3:\"all\";}');
    //$model->setActionsSerialized('a:6:{s:4:\"type\";s:40:\"salesrule/rule_condition_product_combine\";s:9:\"attribute\";N;s:8:\"operator\";N;s:5:\"value\";s:1:\"1\";s:18:\"is_value_processed\";N;s:10:\"aggregator\";s:3:\"all\";}');
    $model->setStopRulesProcessing(0);
    $model->setIsAdvanced(1);
   // $model->setProductIds($productId);
    $model->setSortOrder('0');
    $model->setSimpleAction('by_percent');
    $model->setDiscountAmount($discountprice);
    $model->setDiscountStep(0);
    $model->setSimpleFreeShipping(0);
    $model->setCouponType(2);
    $model->setCouponCode($couponCode);
    $model->setUsesPerCoupon(1);
    $model->setTimesUsed(0);
    $model->setIsRss(0);
    $model->setWebsiteIds('1');
    $model->save();
    }
    echo 'ok';

it fixes the issue If you need only fixed amount discount, then you can remove the validate for Discount Amount field so that you can add negative value in this field, so when you try to apply this coupon it will automatically add that amount instead to decrease. So you need to override below two classes.
For more details on Magento override see this Link.

Mage_Adminhtml_Block_Promo_Quote_Edit_Tab_Actions 

$fieldset->addField('discount_amount', 'text', array(
            'name' => 'discount_amount',
            'required' => true,
            'class' => 'validate-not-negative-number',
            'label' => Mage::helper('salesrule')->__('Discount Amount'),
        ));

$fieldset->addField('discount_amount', 'text', array(
            'name' => 'discount_amount',
            'required' => true,
            'label' => Mage::helper('salesrule')->__('Discount Amount'),
        ));

if ($this->hasDiscountAmount()) {
            if ((int)$this->getDiscountAmount() < 0) {
                Mage::throwException(Mage::helper('rule')->__('Invalid discount amount.'));
            }
        }

Mage_Rule_Model_Abstract::_beforeSave()

fixed the issue. Will look into that further There is an event in magento,
sales_quote_collect_totals_after This is fired whenever your total is calculated, what you can do is set a flag in session on click on the button to apply discount, and in this above event's observer method, check if it is set then apply discount.

<global>
 <events>
   <sales_quote_collect_totals_after>
     <observers>
       <class>Custom_Module_Model_Observer</class>
       <method>collectTotals</method>
     </observers>
   </sales_quote_collect_totals_after>
 </events>
</global>

Custom
  /Module
    /Model
      /Observer.php

public function collectTotals(Varien_Event_Observer $observer)
{
       $quote=$observer->getEvent()->getQuote();
       $quoteid=$quote->getId();
    //check condition here if need to apply Discount
        if($disocuntApply) $discountAmount =5;

     if($quoteid) {
               if($discountAmount>0) {
           $total=$quote->getBaseSubtotal();
           $quote->setSubtotal(0);
           $quote->setBaseSubtotal(0);

           $quote->setSubtotalWithDiscount(0);
           $quote->setBaseSubtotalWithDiscount(0);

           $quote->setGrandTotal(0);
           $quote->setBaseGrandTotal(0);


           $canAddItems = $quote->isVirtual()? ('billing') : ('shipping'); 
           foreach ($quote->getAllAddresses() as $address) {

                    $address->setSubtotal(0);
                    $address->setBaseSubtotal(0);

                    $address->setGrandTotal(0);
                    $address->setBaseGrandTotal(0);

                    $address->collectTotals();

                    $quote->setSubtotal((float) $quote->getSubtotal() + $address->getSubtotal());
                    $quote->setBaseSubtotal((float) $quote->getBaseSubtotal() + $address->getBaseSubtotal());

                    $quote->setSubtotalWithDiscount(
                        (float) $quote->getSubtotalWithDiscount() + $address->getSubtotalWithDiscount()
                    );
                    $quote->setBaseSubtotalWithDiscount(
                        (float) $quote->getBaseSubtotalWithDiscount() + $address->getBaseSubtotalWithDiscount()
                    );

                    $quote->setGrandTotal((float) $quote->getGrandTotal() + $address->getGrandTotal());
                    $quote->setBaseGrandTotal((float) $quote->getBaseGrandTotal() + $address->getBaseGrandTotal());

           $quote ->save(); 

              $quote->setGrandTotal($quote->getBaseSubtotal()-$discountAmount)
              ->setBaseGrandTotal($quote->getBaseSubtotal()-$discountAmount)
              ->setSubtotalWithDiscount($quote->getBaseSubtotal()-$discountAmount)
              ->setBaseSubtotalWithDiscount($quote->getBaseSubtotal()-$discountAmount)
              ->save(); 


            if($address->getAddressType()==$canAddItems) {

             $address->setSubtotalWithDiscount((float) $address->getSubtotalWithDiscount()-$discountAmount);
             $address->setGrandTotal((float) $address->getGrandTotal()-$discountAmount);
             $address->setBaseSubtotalWithDiscount((float) $address->getBaseSubtotalWithDiscount()-$discountAmount);
             $address->setBaseGrandTotal((float) $address->getBaseGrandTotal()-$discountAmount);
             if($address->getDiscountDescription()){
             $address->setDiscountAmount(-($address->getDiscountAmount()-$discountAmount));
             $address->setDiscountDescription($address->getDiscountDescription().', Amount Waived');
             $address->setBaseDiscountAmount(-($address->getBaseDiscountAmount()-$discountAmount));
             }else {
             $address->setDiscountAmount(-($discountAmount));
             $address->setDiscountDescription('Amount Waived');
             $address->setBaseDiscountAmount(-($discountAmount));
             }
             $address->save();
            }//end: if
           } //end: foreach
           //echo $quote->getGrandTotal();

          foreach($quote->getAllItems() as $item){
                         //We apply discount amount based on the ratio between the GrandTotal and the RowTotal
                         $rat=$item->getPriceInclTax()/$total;
                         $ratdisc=$discountAmount*$rat;
                         $item->setDiscountAmount(($item->getDiscountAmount()+$ratdisc) * $item->getQty());
                         $item->setBaseDiscountAmount(($item->getBaseDiscountAmount()+$ratdisc) * $item->getQty())->save();

                       }


                    }

            }
         }

With these it helps I have a coupon code (XYZ25) in woocommerce which include 25% off and maximum discount is Rs.250. ,
Since Woocommerce 3.2 or 3.3, this code doesn't work anymore

add_action( 'woocommerce_calculate_totals', 'coupon_discount_max_switch', 10, 1);
function coupon_discount_max_switch( $cart_obj ) {

    if ( is_admin() && ! defined( 'DOING_AJAX' ) )
        return;

    // Set HERE your 2 coupons slugs  <===  <===  <===  <===  <===  <===  <===  <===  <===
    $coupon_25_percent = 'xyz25';
    $coupon_25_fixed = 'fix250';

    // Set HERE the limit amount  <===  <===  <===  <===  <===  <===  <===  <===  <===  <===
    $limit = 250; // Without VAT

    $total_discount = $cart_obj->get_cart_discount_total(); // Total cart discount

    // When 'xyz25' is set and the total discount is reached
    if( $cart_obj->has_discount( $coupon_25_percent ) && $limit_icl_vat <= $total_discount ){
        // Remove the 'xyz25' coupon
        $cart_obj->remove_coupon( $coupon_25_percent );
        // Checking that the fixed dicount is not already set.
        if( ! $cart_obj->has_discount( $coupon_25_fixed ) ){
            // Add the 'fix250' coupon
            $cart_obj->add_discount( $coupon_25_fixed );

            // Displaying a custom message
            $message = __( "The cart discount limit of Rs.$limit is reached", "woocommerce" );
            wc_add_notice( $message, 'notice' );
        }
    } 
}