diff --git a/conektaprestashop.php b/conektaprestashop.php
index 5062f8886..4eab8f3a7 100755
--- a/conektaprestashop.php
+++ b/conektaprestashop.php
@@ -237,7 +237,7 @@ private function _createPendingCashState()
      */
     public function uninstall()
     {
-        return parent::uninstall() && Configuration::deleteByName('CONEKTA_PRESTASHOP_VERSION') && Configuration::deleteByName('CONEKTA_MSI') && Configuration::deleteByName('CONEKTA_CARDS') && Configuration::deleteByName('CONEKTA_CASH') && Configuration::deleteByName('CONEKTA_BANORTE') && Configuration::deleteByName('CONEKTA_SPEI') && Configuration::deleteByName('CONEKTA_PUBLIC_KEY_TEST') && Configuration::deleteByName('CONEKTA_PUBLIC_KEY_LIVE') && Configuration::deleteByName('CONEKTA_MODE') && Configuration::deleteByName('CONEKTA_PRIVATE_KEY_TEST') && Configuration::deleteByName('CONEKTA_PRIVATE_KEY_LIVE') && Configuration::deleteByName('CONEKTA_PAYMENT_ORDER_STATUS') && Configuration::deleteByName('CONEKTA_WEBHOOK') && Configuration::deleteByName('CONEKTA_WEBHOOK_FAILED_ATTEMPTS') && Configuration::deleteByName('CONEKTA_WEBHOOK_ERROR_MESSAGE') && Configuration::deleteByName('CONEKTA_WEBHOOK_FAILED_URL') && Db::getInstance()->Execute('DROP TABLE IF EXISTS `' . _DB_PREFIX_ . 'conekta_customer`') && Db::getInstance()->Execute('DROP TABLE IF EXISTS `' . _DB_PREFIX_ . 'conekta_transaction`');
+        return parent::uninstall() && Configuration::deleteByName('CONEKTA_PRESTASHOP_VERSION') && Configuration::deleteByName('CONEKTA_MSI') && Configuration::deleteByName('CONEKTA_CARDS') && Configuration::deleteByName('CONEKTA_CASH') && Configuration::deleteByName('CONEKTA_BANORTE') && Configuration::deleteByName('CONEKTA_SPEI') && Configuration::deleteByName('CONEKTA_PUBLIC_KEY_TEST') && Configuration::deleteByName('CONEKTA_PUBLIC_KEY_LIVE') && Configuration::deleteByName('CONEKTA_MODE') && Configuration::deleteByName('CONEKTA_PRIVATE_KEY_TEST') && Configuration::deleteByName('CONEKTA_PRIVATE_KEY_LIVE') && Configuration::deleteByName('CONEKTA_SIGNATURE_KEY_LIVE') && Configuration::deleteByName('CONEKTA_SIGNATURE_KEY_TEST') && Configuration::deleteByName('CONEKTA_PAYMENT_ORDER_STATUS') && Configuration::deleteByName('CONEKTA_WEBHOOK') && Configuration::deleteByName('CONEKTA_WEBHOOK_FAILED_ATTEMPTS') && Configuration::deleteByName('CONEKTA_WEBHOOK_ERROR_MESSAGE') && Configuration::deleteByName('CONEKTA_WEBHOOK_FAILED_URL') && Db::getInstance()->Execute('DROP TABLE IF EXISTS `' . _DB_PREFIX_ . 'conekta_customer`') && Db::getInstance()->Execute('DROP TABLE IF EXISTS `' . _DB_PREFIX_ . 'conekta_transaction`');
     }
 
     /**
@@ -602,11 +602,13 @@ public function processPayment($token, $type, $monthly_installments)
                     array(
                         'source' => array(
                             'type'                 => 'card',
-                            'token_id'             => $token,
-                            'monthly_installments' => $monthly_installments > 1 ? $monthly_installments : null
+                            'token_id'             => $token
                           ),
                          'amount' => $amount
                      );
+                if($monthly_installments > 1){
+                    array_merge($charge_params->source, array('monthly_installments' => $monthly_installments)) ;   
+                }    
                 $charge_response = $order->createCharge($charge_params);
                 $order_status = (int)Configuration::get('PS_OS_PAYMENT');
                 $message = $this->l('Conekta Transaction Details:') . "\n\n" . $this->l('Amount:') . ' ' . ($charge_response->amount * 0.01) . "\n" . $this->l('Status:') . ' ' . ($charge_response->status == 'paid' ? $this->l('Paid') : $this->l('Unpaid')) . "\n" . $this->l('Processed on:') . ' ' . strftime('%Y-%m-%d %H:%M:%S', $charge_response->created_at) . "\n" . $this->l('Currency:') . ' ' . Tools::strtoupper($charge_response->currency) . "\n" . $this->l('Mode:') . ' ' . ($charge_response->livemode == 'true' ? $this->l('Live') : $this->l('Test')) . "\n";
@@ -770,16 +772,18 @@ public function getContent()
 
         if ($submitConfigEvent) {
             $configuration_values = array(
-                'CONEKTA_MODE' => Tools::getValue('conekta_mode') ,
-                'CONEKTA_PUBLIC_KEY_TEST' => rtrim(Tools::getValue('conekta_public_key_test')) ,
-                'CONEKTA_PUBLIC_KEY_LIVE' => rtrim(Tools::getValue('conekta_public_key_live')) ,
-                'CONEKTA_PRIVATE_KEY_TEST' => rtrim(Tools::getValue('conekta_private_key_test')) ,
-                'CONEKTA_PRIVATE_KEY_LIVE' => rtrim(Tools::getValue('conekta_private_key_live')) ,
-                'CONEKTA_CARDS' => rtrim(Tools::getValue('conekta_cards')) ,
-                'CONEKTA_MSI' => rtrim(Tools::getValue('conekta_msi')) ,
-                'CONEKTA_CASH' => rtrim(Tools::getValue('conekta_cash')) ,
-                'CONEKTA_BANORTE' => rtrim(Tools::getValue('conekta_banorte')) ,
-                'CONEKTA_SPEI' => rtrim(Tools::getValue('conekta_spei'))
+                'CONEKTA_MODE'               => Tools::getValue('conekta_mode') ,
+                'CONEKTA_PUBLIC_KEY_TEST'    => rtrim(Tools::getValue('conekta_public_key_test')) ,
+                'CONEKTA_PUBLIC_KEY_LIVE'    => rtrim(Tools::getValue('conekta_public_key_live')) ,
+                'CONEKTA_PRIVATE_KEY_TEST'   => rtrim(Tools::getValue('conekta_private_key_test')) ,
+                'CONEKTA_PRIVATE_KEY_LIVE'   => rtrim(Tools::getValue('conekta_private_key_live')) ,
+                'CONEKTA_CARDS'              => rtrim(Tools::getValue('conekta_cards')) ,
+                'CONEKTA_MSI'                => rtrim(Tools::getValue('conekta_msi')) ,
+                'CONEKTA_CASH'               => rtrim(Tools::getValue('conekta_cash')) ,
+                'CONEKTA_BANORTE'            => rtrim(Tools::getValue('conekta_banorte')) ,
+                'CONEKTA_SPEI'               => rtrim(Tools::getValue('conekta_spei')),
+                'CONEKTA_SIGNATURE_KEY_TEST' => rtrim(Tools::getValue('conekta_signature_key_test')),
+                'CONEKTA_SIGNATURE_KEY_LIVE' => rtrim(Tools::getValue('conekta_signature_key_live'))
                 );
 
             foreach ($configuration_values as $configuration_key => $configuration_value) {
@@ -829,6 +833,8 @@ public function getContent()
         $this->smarty->assign("conekta_private_key_test", Configuration::get('CONEKTA_PRIVATE_KEY_TEST'));
         $this->smarty->assign("conekta_public_key_live", Configuration::get('CONEKTA_PUBLIC_KEY_LIVE'));
         $this->smarty->assign("conekta_private_key_live", Configuration::get('CONEKTA_PRIVATE_KEY_LIVE'));
+        $this->smarty->assign("conekta_signature_key_test", Configuration::get('CONEKTA_SIGNATURE_KEY_TEST'));
+        $this->smarty->assign("conekta_signature_key_live", Configuration::get('CONEKTA_SIGNATURE_KEY_LIVE'));
 
 
         $this->smarty->assign("url", $url);
diff --git a/notification.php b/notification.php
index cab4fd516..c295001ec 100755
--- a/notification.php
+++ b/notification.php
@@ -20,6 +20,7 @@
 // To configure, add webhook in account storename.com/modules/conektaefectivo/notification.php
 
 $body = Tools::file_get_contents('php://input');
+authenticateEvent($body, $_SERVER['HTTP_DIGEST']);
 $event_json = Tools::jsonDecode($body);
 
 if ($event_json->type == 'charge.paid') {
@@ -46,5 +47,32 @@
     }
 }
 
+function authenticateEvent($body, $digest) {
+    if (Configuration::get('CONEKTA_MODE')) {
+            $private_key_string = Configuration::get('CONEKTA_SIGNATURE_KEY_LIVE');
+        } else {
+            $private_key_string = Configuration::get('CONEKTA_SIGNATURE_KEY_TEST');
+        }
+    if (!empty($private_key_string) && !empty($body)) {
+      if (!empty($digest)) {
+        $private_key = openssl_pkey_get_private($private_key_string);
+        $encrypted_message = base64_decode($digest);
+        $sha256_message = "";
+        openssl_private_decrypt($encrypted_message, $sha256_message, $private_key);
+        if (hash("sha256", $body) != $sha256_message) {
+            authenticateLogger("unauthenticated event");
+        }
+      } else {
+        authenticateLogger("Empty digest");
+      }
+    }
+  }
+
+  function authenticateLogger($log_message){
+    if (version_compare(_PS_VERSION_, '1.4.0.3', '>') && class_exists('Logger')) {
+        Logger::addLog($log_message, 1, null,'notification', '');
+    }
+  }
+
 header('HTTP/1.1 200 OK');
 exit;
diff --git a/views/templates/hook/content.tpl b/views/templates/hook/content.tpl
index e16898c46..6314f4ccb 100755
--- a/views/templates/hook/content.tpl
+++ b/views/templates/hook/content.tpl
@@ -137,6 +137,24 @@
 					<input name="conekta_public_key_live" value="{$conekta_public_key_live|escape:'htmlall':'UTF-8'}" type="text">
 				</div>			
 			</div>
+			<div class="form-group">
+				<label class="control-label col-lg-3">
+					{l s='Signature Test Key' mod='conektaprestashop'}
+				</label>
+				<div class="col-lg-3">
+					<textarea name="conekta_signature_key_test" class="form-control" rows="5" value="" type="text">{$conekta_signature_key_test|escape:'htmlall':'UTF-8'}</textarea>
+				</div>		
+			</div>
+			<div class="form-group">
+				<label class="control-label col-lg-3">
+					{l s='Signature Live Key' mod='conektaprestashop'}
+				</label>
+				<div class="col-lg-3">
+					<textarea name="conekta_signature_key_live" class="form-control" rows="5" value="" type="text">
+					{$conekta_signature_key_live|escape:'htmlall':'UTF-8'}
+					</textarea>	
+				</div>		
+			</div>
 		</div>
 
 		<div class="panel-footer">