Developers MUST use .* to denote a wildcard subscription. Just having a * at the end of channel names will NOT get translated to .* and will result in a subscribe error. 

Here is an example of a proper wildcard subscribe which results in subscribing to all channels of that are prefixed with 'stocks.', like '', '', '', etc.

pubnub.subscribe({ channels: ['stocks.*'] });

For more details on proper code syntax, consult the official docs for the SDK. Once you choose the SDK, navigate to Tutorials, then to Stream Controller and look for Wildcard Subscribe. Here are the Wildcard Subscribe docs for the JavaScript SDK.