title: Attempting to add dyno to app hosted with Heroku hobby plan raises error
body: <p>I have a Flask app running on Heroku Hobby - 1 Dyno. When I try to scale my app to 2 dynos I receive this error: "Cannot update to more than 1 Hobby size dynos per process type." The hobby plan says it allows multiple dynos. Why am I getting this error?</p>
  
  <pre><code>heroku ps:scale web=2
  </code></pre>
  
  <p><code>Procfile</code>:</p>
  
  <pre><code>web: gunicorn main:app
  </code></pre>