diff --git a/tests/test_preference.py b/tests/test_preference.py
index b9281f9..82c4cb4 100644
--- a/tests/test_preference.py
+++ b/tests/test_preference.py
@@ -4,6 +4,7 @@
 import unittest
 
 import mercadopago
+import time
 
 
 class TestPreference(unittest.TestCase):
@@ -33,18 +34,22 @@ def test_all(self):
         preference_saved = self.sdk.preference().create(preference_object)
         self.assertEqual(preference_saved["status"], 201)
 
+        time.sleep(1)
+
         preference_object["items"][0]["title"] = "Testando 1 2 3"
 
         preference_update = self.sdk.preference().update(
             preference_saved["response"]["id"], preference_object)
         self.assertEqual(preference_update["status"], 200)
 
+        time.sleep(1)
         preference_saved = self.sdk.preference().get(
             preference_saved["response"]["id"])
 
         self.assertEqual(preference_saved["response"]["items"][0]["title"],
                          preference_object["items"][0]["title"])
 
+        time.sleep(1)
         preference_saved = self.sdk.preference().search()
 
         self.assertEqual(preference_saved["response"]["elements"][0]["items"][0],
diff --git a/tests/test_subscription.py b/tests/test_subscription.py
index d4ee7bd..43c9f99 100644
--- a/tests/test_subscription.py
+++ b/tests/test_subscription.py
@@ -114,7 +114,7 @@ def test_create_subscriptions_without_a_plan(self):
     @classmethod
     def create_card_token(cls):
         card_token_object = {
-            "card_number": "4074090000000004",
+            "card_number": "5031433215406351",
             "security_code": "123",
             "expiration_year": datetime.now().strftime("%Y"),
             "expiration_month": "12",