diff --git a/.github/workflows/craftgate-build.yml b/.github/workflows/craftgate-build.yml
index f8a397d..ed7b61d 100644
--- a/.github/workflows/craftgate-build.yml
+++ b/.github/workflows/craftgate-build.yml
@@ -39,7 +39,7 @@ jobs:
         run: python -m compileall craftgate
 
       - name: Run unit tests
-        run: python -m unittest tests.test_idempotency -v
+        run: python -m unittest tests.test_idempotency tests.test_hook_sample -v
 
       - name: Build distribution and verify metadata
         if: matrix.python-version == '3.12'
diff --git a/craftgate/adapter/hook_adapter.py b/craftgate/adapter/hook_adapter.py
index acd30ee..a04b4a8 100644
--- a/craftgate/adapter/hook_adapter.py
+++ b/craftgate/adapter/hook_adapter.py
@@ -16,10 +16,13 @@ def is_webhook_verified(self, merchant_hook_key: str, incoming_signature: str, w
         if merchant_hook_key is None or incoming_signature is None or webhook_data is None:
             return False
 
+        event_type = getattr(webhook_data.event_type, "value", webhook_data.event_type)
+        status = getattr(webhook_data.status, "value", webhook_data.status)
+
         data = "{}{}{}{}".format(
-            webhook_data.event_type,
+            event_type,
             webhook_data.event_timestamp,
-            webhook_data.status,
+            status,
             webhook_data.payload_id
         )
 
diff --git a/tests/test_hook_sample.py b/tests/test_hook_sample.py
index 5ec47bc..e3895e4 100644
--- a/tests/test_hook_sample.py
+++ b/tests/test_hook_sample.py
@@ -47,6 +47,30 @@ def test_should_not_verify_webhook_signature(self):
         is_verified = self.hook.is_webhook_verified(merchant_hook_key, incoming_signature, webhook_data)
         self.assertFalse(is_verified)
 
+    def test_should_verify_webhook_signature_with_string_values(self):
+        merchant_hook_key = "Aoh7tReTybO6wOjBmOJFFsOR53SBojEp"
+        incoming_signature = "0wRB5XqWJxwwPbn5Z9TcbHh8EGYFufSYTsRMB74N094="
+        webhook_data = WebhookData(
+            event_type="API_VERIFY_AND_AUTH",
+            event_time=datetime(2025, 7, 21, 16, 40, 21, 395655),
+            event_timestamp=1661521221,
+            status="SUCCESS",
+            payload_id="584"
+        )
+        is_verified = self.hook.is_webhook_verified(merchant_hook_key, incoming_signature, webhook_data)
+        self.assertTrue(is_verified)
+
+    def test_should_return_false_when_arguments_are_none(self):
+        webhook_data = WebhookData(
+            event_type=WebhookEventType.API_VERIFY_AND_AUTH,
+            event_timestamp=1661521221,
+            status=WebhookStatus.SUCCESS,
+            payload_id="584"
+        )
+        self.assertFalse(self.hook.is_webhook_verified(None, "sig", webhook_data))
+        self.assertFalse(self.hook.is_webhook_verified("key", None, webhook_data))
+        self.assertFalse(self.hook.is_webhook_verified("key", "sig", None))
+
 
 if __name__ == "__main__":
     unittest.main()