diff --git a/docs/user/cards.rst b/docs/user/cards.rst
index 9c7a369..957f2db 100644
--- a/docs/user/cards.rst
+++ b/docs/user/cards.rst
@@ -31,7 +31,7 @@ Lets dive into a simple example that sends a card to a room
     card = AdaptiveCard(body=[greeting, first_name, age], actions=[submit])
 
     api = WebexTeamsAPI()
-    api.messages.create(text="fallback", roomId="...", cards=card)
+    api.messages.create(text="fallback", roomId="...", attachments=[card])
 
 The message we send with this code then looks like this in our Webex Teams
 client:
diff --git a/webexteamssdk/api/messages.py b/webexteamssdk/api/messages.py
index b0a9916..c38b561 100644
--- a/webexteamssdk/api/messages.py
+++ b/webexteamssdk/api/messages.py
@@ -200,7 +200,7 @@ def create(self, roomId=None, toPersonId=None, toPersonEmail=None,
             for item, attachment in enumerate(attachments):
                 check_type(attachment, (dict, AdaptiveCard))
 
-                if isinstance(attachments, AdaptiveCard):
+                if isinstance(attachment, AdaptiveCard):
                     attachments[item] = make_attachment(attachment)
 
         post_data = dict_from_items_with_values(