diff --git a/alma/composer.json b/alma/composer.json
index 94bf843a..72b1b29f 100644
--- a/alma/composer.json
+++ b/alma/composer.json
@@ -11,7 +11,7 @@
     },
     "require": {
         "php": "^5.6 || ~7.0 || ~7.1 || ~7.2 || ~7.3 || ~7.4 || ~8.0 || ~8.1",
-        "alma/alma-php-client": "^2.1.0",
+        "alma/alma-php-client": "^2.2.0",
         "ext-json": "*",
         "ext-openssl": "*",
         "prestashop/prestashop-accounts-installer": "^v1.0.4",
diff --git a/alma/controllers/front/ipn.php b/alma/controllers/front/ipn.php
index 496c4641..7eff5931 100644
--- a/alma/controllers/front/ipn.php
+++ b/alma/controllers/front/ipn.php
@@ -23,7 +23,8 @@
  */
 
 use Alma\PrestaShop\API\MismatchException;
-use Alma\PrestaShop\Exceptions\RefundException;
+use Alma\PrestaShop\Builders\Validators\PaymentValidationBuilder;
+use Alma\PrestaShop\Exceptions\PaymentValidationException;
 use Alma\PrestaShop\Logger;
 use Alma\PrestaShop\Traits\AjaxTrait;
 use Alma\PrestaShop\Validators\PaymentValidation;
@@ -40,8 +41,21 @@ class AlmaIpnModuleFrontController extends ModuleFrontController
 {
     use AjaxTrait;
 
+    /**
+     * @var bool
+     */
     public $ssl = true;
 
+    /**
+     * @var Context
+     */
+    public $context;
+
+    /**
+     * @var PaymentValidation
+     */
+    protected $paymentValidation;
+
     /**
      * IPN constructor
      *
@@ -51,14 +65,14 @@ public function __construct()
     {
         parent::__construct();
         $this->context = Context::getContext();
+        $paymentValidationBuilder = new PaymentValidationBuilder();
+        $this->paymentValidation = $paymentValidationBuilder->getInstance();
     }
 
     /**
      * @return void
      *
      * @throws PrestaShopException
-     * @throws RefundException
-     * @throws MismatchException
      */
     public function postProcess()
     {
@@ -67,10 +81,14 @@ public function postProcess()
         header('Content-Type: application/json');
 
         $paymentId = Tools::getValue('pid');
-        $validator = new PaymentValidation($this->context, $this->module);
 
         try {
-            $validator->validatePayment($paymentId);
+            $this->paymentValidation->checkSignature($paymentId, Configuration::get('ALMA_API_KEY'), $_SERVER['HTTP_X_ALMA_SIGNATURE']);
+            $this->paymentValidation->validatePayment($paymentId);
+            $this->ajaxRenderAndExit(json_encode(['success' => true]));
+        } catch (PaymentValidationException $e) {
+            Logger::instance()->error('[Alma] IPN Payment Validation Error - Message : ' . $e->getMessage());
+            $this->ajaxRenderAndExit(json_encode(['error' => $e->getMessage()]), 500);
         } catch (PaymentValidationError $e) {
             Logger::instance()->error('ipn payment_validation_error - Message : ' . $e->getMessage());
             $this->ajaxRenderAndExit(json_encode(['error' => $e->getMessage()]), 500);
@@ -78,7 +96,5 @@ public function postProcess()
             Logger::instance()->error('ipn payment_validation_mismatch_error - Message : ' . $e->getMessage());
             $this->ajaxRenderAndExit(json_encode(['error' => $e->getMessage()]), 200);
         }
-
-        $this->ajaxRenderAndExit(json_encode(['success' => true]));
     }
 }
diff --git a/alma/controllers/front/validation.php b/alma/controllers/front/validation.php
index ff72fa56..f6ba1b6e 100644
--- a/alma/controllers/front/validation.php
+++ b/alma/controllers/front/validation.php
@@ -22,6 +22,8 @@
  * @license   https://opensource.org/licenses/MIT The MIT License
  */
 
+use Alma\PrestaShop\API\MismatchException;
+use Alma\PrestaShop\Exceptions\PaymentValidationException;
 use Alma\PrestaShop\Logger;
 use Alma\PrestaShop\Validators\PaymentValidation;
 use Alma\PrestaShop\Validators\PaymentValidationError;
@@ -72,7 +74,10 @@ public function postProcess()
         } catch (PaymentValidationError $e) {
             Logger::instance()->error('payment_validation_error - Message : ' . $e->getMessage());
             $redirect_to = $this->fail($e->cart, $e->getMessage());
-        } catch (Exception $e) {
+        } catch (PaymentValidationException $e) {
+            Logger::instance()->error('payment_validation_error - Message : ' . $e->getMessage());
+            $redirect_to = $this->fail($e->cartId, $e->getMessage());
+        } catch (MismatchException $e) {
             Logger::instance()->error('payment_error - Message : ' . $e->getMessage());
             $redirect_to = $this->fail(null, $e->getMessage());
         }
diff --git a/alma/exceptions/PaymentValidationException.php b/alma/exceptions/PaymentValidationException.php
new file mode 100644
index 00000000..ac662060
--- /dev/null
+++ b/alma/exceptions/PaymentValidationException.php
@@ -0,0 +1,43 @@
+<?php
+/**
+ * 2018-2024 Alma SAS.
+ *
+ * THE MIT LICENSE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+ * documentation files (the "Software"), to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
+ * to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+ * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+ * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * @author    Alma SAS <contact@getalma.eu>
+ * @copyright 2018-2024 Alma SAS
+ * @license   https://opensource.org/licenses/MIT The MIT License
+ */
+
+namespace Alma\PrestaShop\Exceptions;
+
+if (!defined('_PS_VERSION_')) {
+    exit;
+}
+
+class PaymentValidationException extends AlmaException
+{
+    /**
+     * @var int
+     */
+    public $cartId;
+
+    public function __construct($message = '', $cartId = -1, $code = 0, $previous = null)
+    {
+        parent::__construct($message, $code, $previous);
+        $this->cartId = $cartId;
+    }
+}
diff --git a/alma/lib/Builders/Validators/PaymentValidationBuilder.php b/alma/lib/Builders/Validators/PaymentValidationBuilder.php
new file mode 100644
index 00000000..cab41b4a
--- /dev/null
+++ b/alma/lib/Builders/Validators/PaymentValidationBuilder.php
@@ -0,0 +1,52 @@
+<?php
+/**
+ * 2018-2024 Alma SAS.
+ *
+ * THE MIT LICENSE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+ * documentation files (the "Software"), to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
+ * to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+ * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+ * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * @author    Alma SAS <contact@getalma.eu>
+ * @copyright 2018-2024 Alma SAS
+ * @license   https://opensource.org/licenses/MIT The MIT License
+ */
+
+namespace Alma\PrestaShop\Builders\Validators;
+
+use Alma\PrestaShop\Traits\BuilderTrait;
+use Alma\PrestaShop\Validators\PaymentValidation;
+
+if (!defined('_PS_VERSION_')) {
+    exit;
+}
+
+/**
+ * PaymentValidationBuilder.
+ */
+class PaymentValidationBuilder
+{
+    use BuilderTrait;
+
+    /**
+     * @return PaymentValidation
+     */
+    public function getInstance()
+    {
+        return new PaymentValidation(
+            $this->getContextFactory(),
+            $this->getModuleFactory(),
+            $this->getClientPaymentValidator()
+        );
+    }
+}
diff --git a/alma/lib/Helpers/ShareOfCheckoutHelper.php b/alma/lib/Helpers/ShareOfCheckoutHelper.php
index c4652c8d..d87b95d5 100644
--- a/alma/lib/Helpers/ShareOfCheckoutHelper.php
+++ b/alma/lib/Helpers/ShareOfCheckoutHelper.php
@@ -185,8 +185,6 @@ public function isSocActivated()
             || empty($shareOfCheckoutEnabledDate)
             || !$this->dateHelper->isValidTimeStamp($shareOfCheckoutEnabledDate)
         ) {
-            Logger::instance()->info('Share Of Checkout is disabled or invalide date');
-
             return false;
         }
 
diff --git a/alma/lib/Traits/BuilderTrait.php b/alma/lib/Traits/BuilderTrait.php
index e5b76462..99157931 100644
--- a/alma/lib/Traits/BuilderTrait.php
+++ b/alma/lib/Traits/BuilderTrait.php
@@ -24,6 +24,7 @@
 
 namespace Alma\PrestaShop\Traits;
 
+use Alma\API\Lib\PaymentValidator;
 use Alma\PrestaShop\Factories\AddressFactory;
 use Alma\PrestaShop\Factories\CarrierFactory;
 use Alma\PrestaShop\Factories\CartFactory;
@@ -1202,4 +1203,12 @@ public function getInsuranceApiService($insuranceApiService = null)
 
         return new InsuranceApiService();
     }
+
+    /**
+     * @return PaymentValidator
+     */
+    public function getClientPaymentValidator()
+    {
+        return new PaymentValidator();
+    }
 }
diff --git a/alma/lib/Validators/PaymentValidation.php b/alma/lib/Validators/PaymentValidation.php
index 0ef180bb..c782c1c3 100644
--- a/alma/lib/Validators/PaymentValidation.php
+++ b/alma/lib/Validators/PaymentValidation.php
@@ -25,11 +25,14 @@
 namespace Alma\PrestaShop\Validators;
 
 use Alma\API\Entities\Payment;
+use Alma\API\Lib\PaymentValidator;
 use Alma\API\RequestError;
 use Alma\PrestaShop\API\MismatchException;
 use Alma\PrestaShop\Builders\Helpers\PriceHelperBuilder;
 use Alma\PrestaShop\Builders\Helpers\SettingsHelperBuilder;
 use Alma\PrestaShop\Builders\Services\OrderServiceBuilder;
+use Alma\PrestaShop\Exceptions\PaymentValidationException;
+use Alma\PrestaShop\Exceptions\RefundException;
 use Alma\PrestaShop\Helpers\ClientHelper;
 use Alma\PrestaShop\Helpers\PriceHelper;
 use Alma\PrestaShop\Helpers\RefundHelper;
@@ -68,15 +71,23 @@ class PaymentValidation
      * @var OrderService
      */
     protected $orderService;
+    /**
+     * @var PaymentValidator
+     */
+    protected $paymentValidator;
 
     /**
      * @param $context
      * @param $module
      */
-    public function __construct($context, $module)
-    {
+    public function __construct(
+        $context,
+        $module,
+        $clientPaymentValidator
+    ) {
         $this->context = $context;
         $this->module = $module;
+        $this->paymentValidator = $clientPaymentValidator;
 
         $settingsHelperBuilder = new SettingsHelperBuilder();
         $this->settingsHelper = $settingsHelperBuilder->getInstance();
@@ -120,6 +131,7 @@ private function isValidCurrency()
      *
      * @throws MismatchException
      * @throws PaymentValidationError
+     * @throws PaymentValidationException
      */
     public function validatePayment($almaPaymentId)
     {
@@ -210,7 +222,11 @@ public function validatePayment($almaPaymentId)
 
                 $clientHelper = new ClientHelper();
                 $refundHelper = new RefundHelper($this->module, $cart, $payment->id, $clientHelper);
-                $refundHelper->mismatchFullRefund();
+                try {
+                    $refundHelper->mismatchFullRefund();
+                } catch (RefundException $e) {
+                    throw new PaymentValidationException('[Alma] Error refund from mismatch', $cart->id, 0, $e);
+                }
             }
 
             $firstInstalment = $payment->payment_plan[0];
@@ -312,6 +328,8 @@ public function validatePayment($almaPaymentId)
      * @param $cartId
      *
      * @return \OrderCore|null
+     *
+     * @throws PaymentValidationException
      */
     private function getOrderByCartId($cartId)
     {
@@ -320,7 +338,13 @@ private function getOrderByCartId($cartId)
         } else {
             $orderId = (int) \Order::getOrderByCartId((int) $cartId);
 
-            return new \Order($orderId);
+            try {
+                return new \Order($orderId);
+            } catch (\PrestaShopDatabaseException $e) {
+                throw new PaymentValidationException('[Alma] Error Prestashop database', $cartId, 0, $e);
+            } catch (\PrestaShopException $e) {
+                throw new PaymentValidationException('[Alma] Error Prestashop', $cartId, 0, $e);
+            }
         }
     }
 
@@ -330,7 +354,7 @@ private function getOrderByCartId($cartId)
      * When calculating cart amount from an IPN call.
      *
      * @param \Cart $cart
-     * @param \Customer $cart
+     * @param \Customer $customer
      *
      * @return float
      */
@@ -347,4 +371,27 @@ private function getCartTotals($cart, $customer)
 
         return $cartTotals;
     }
+
+    /**
+     * @param string $paymentId
+     * @param string $apiKey
+     * @param string $signature
+     *
+     * @throws PaymentValidationException
+     */
+    public function checkSignature($paymentId, $apiKey, $signature)
+    {
+        if (!$paymentId) {
+            throw new PaymentValidationException('[Alma] Payment ID is missing');
+        }
+        if (!$apiKey) {
+            throw new PaymentValidationException('[Alma] Api key is missing');
+        }
+        if (!$signature) {
+            throw new PaymentValidationException('[Alma] Signature is missing');
+        }
+        if (!$this->paymentValidator->isHmacValidated($paymentId, $apiKey, $signature)) {
+            throw new PaymentValidationException('[Alma] Signature is invalid');
+        }
+    }
 }
diff --git a/alma/lib/Validators/PaymentValidationError.php b/alma/lib/Validators/PaymentValidationError.php
index 451f528c..f383fae1 100644
--- a/alma/lib/Validators/PaymentValidationError.php
+++ b/alma/lib/Validators/PaymentValidationError.php
@@ -28,6 +28,11 @@
     exit;
 }
 
+/**
+ * Class PaymentValidationError.
+ *
+ * @deprecated Use PaymentValidationException instead
+ */
 class PaymentValidationError extends \Exception
 {
     public $cart;
diff --git a/alma/tests/Unit/Validators/PaymentValidationTest.php b/alma/tests/Unit/Validators/PaymentValidationTest.php
new file mode 100644
index 00000000..71bfcc48
--- /dev/null
+++ b/alma/tests/Unit/Validators/PaymentValidationTest.php
@@ -0,0 +1,113 @@
+<?php
+
+/**
+ * 2018-2024 Alma SAS.
+ *
+ * THE MIT LICENSE
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated
+ * documentation files (the "Software"), to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and
+ * to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+ * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+ * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
+ * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * @author    Alma SAS <contact@getalma.eu>
+ * @copyright 2018-2024 Alma SAS
+ * @license   https://opensource.org/licenses/MIT The MIT License
+ */
+
+namespace Alma\PrestaShop\Tests\Unit\Validators;
+
+use Alma\API\Lib\PaymentValidator;
+use Alma\PrestaShop\Exceptions\PaymentValidationException;
+use Alma\PrestaShop\Validators\PaymentValidation;
+use PHPUnit\Framework\TestCase;
+
+class PaymentValidationTest extends TestCase
+{
+    const API_KEY = 'api_test_abc123';
+    const PAYMENT_ID = 'payment_abc123';
+    const WRONG_SIGNATURE = 'wrong_signature';
+    const GOOD_SIGNATURE = 'good_signature';
+    /**
+     * @var PaymentValidation
+     */
+    protected $paymentValidation;
+    /**
+     * @var PaymentValidator
+     */
+    protected $clientPaymentValidator;
+
+    public function setUp()
+    {
+        $this->clientPaymentValidator = $this->createMock(PaymentValidator::class);
+        $this->paymentValidation = new PaymentValidation(
+            $this->createMock(\Context::class),
+            $this->createMock(\Module::class),
+            $this->clientPaymentValidator
+        );
+    }
+
+    public function tearDown()
+    {
+        $this->paymentValidation = null;
+    }
+
+    /**
+     * @dataProvider checkSignatureWrongParamsDataProvider
+     *
+     * @throws PaymentValidationException
+     */
+    public function testCheckSignatureWithoutParamsReturnError($paymentId, $apiKey, $signature)
+    {
+        $this->expectException(PaymentValidationException::class);
+        $this->paymentValidation->checkSignature($paymentId, $apiKey, $signature);
+    }
+
+    /**
+     * @throws PaymentValidationException
+     */
+    public function testCheckSignatureWithBadSignatureReturnError()
+    {
+        $this->clientPaymentValidator->expects($this->once())
+            ->method('isHmacValidated')
+            ->with(self::PAYMENT_ID, self::API_KEY, self::WRONG_SIGNATURE)
+            ->willReturn(false);
+        $this->expectException(PaymentValidationException::class);
+        $this->paymentValidation->checkSignature(self::PAYMENT_ID, self::API_KEY, self::WRONG_SIGNATURE);
+    }
+
+    /**
+     * @throws PaymentValidationException
+     */
+    public function testCheckSignatureWithGoodSignature()
+    {
+        $this->clientPaymentValidator->expects($this->once())
+            ->method('isHmacValidated')
+            ->with(self::PAYMENT_ID, self::API_KEY, self::GOOD_SIGNATURE)
+            ->willReturn(true);
+        $this->paymentValidation->checkSignature(self::PAYMENT_ID, self::API_KEY, self::GOOD_SIGNATURE);
+    }
+
+    /**
+     * @return array[]
+     */
+    public function checkSignatureWrongParamsDataProvider()
+    {
+        return [
+            'Without api key' => [self::PAYMENT_ID, '', self::GOOD_SIGNATURE],
+            'Without payement id' => ['', self::API_KEY, self::GOOD_SIGNATURE],
+            'Without signature' => [self::PAYMENT_ID, self::API_KEY, ''],
+            'With api key null' => [self::PAYMENT_ID, null, self::GOOD_SIGNATURE],
+            'With payement id null' => [null, self::API_KEY, self::GOOD_SIGNATURE],
+            'With signature null' => [self::PAYMENT_ID, self::API_KEY, null],
+        ];
+    }
+}