title: Laravel Echo not subscribing to private Channel
body: <ul>
  <li>Echo Version: 1.8.0</li>
  <li>Laravel Version: 7.0</li>
  <li>PHP Version: 7.2.</li>
  <li>NPM Version: 6.12.1</li>
  <li>Node Version: 12.13.1</li>
  </ul>
  <h3>Description: I'm trying to send notifications to users,</h3>
  <p>My pusher connection is good because it sends on public channels
  And also, i get this message on my console
  <code>[2020-07-24 21:08:09][355] Processed:  Illuminate\Notifications\Events\BroadcastNotificationCreated</code>
  and on pusher i also see that the message was sent.
  I also don't get any errors on my browser console as all the websocket connections are working well.
  But i still dont get any messages.
  I tried</p>
  <pre><code>Echo.private('App.User.' +userId)
     .notification((notification) =&gt; {
     console.log(notification);
    });
  </code></pre>
  <p>I also tried</p>
  <pre><code>Echo.private('App.User.' + userId)
    .listen('.Illuminate\\Notifications\\Events\\BroadcastNotificationCreated', (e) =&gt; {
    console.log('Event Notification received ', e)
    });
  </code></pre>
  <p>Now I turned on Pusher error logging and i got
  <code>app.js:42600 Pusher :  : [&quot;JSON returned from auth endpoint was invalid, yet status code was 200. Data was: &lt;!DOCTYPE html&gt;\r\n&lt;html lang=\&quot;en\&quot;&gt;\r\n  </code></p>
  <p>I also followed many tutorials and the docs
  All to no avail.</p>
  <h3>Steps To Reproduce:</h3>
  <p>Create a notification and declare both the toArray method and toBroadcast methods but echo fails to catch messages from pusher</p>