title: Github authenticates but will not allow code push
body: <p>I am the owner for the "project" repo, but somehow I am not able to push to it.</p>
  
  <pre><code>user@none ~/rails_projects/project $ git remote -v
  origin  git@github.com:user/project.git (fetch)
  origin  git@github.com:user/project.git (push)
  </code></pre>
  
  <p>Here is authentication check:</p>
  
  <pre><code>user@none ~/rails_projects/project $ ssh -T git@github.com
  Hi user/project! You've successfully authenticated, but GitHub does not provide shell access.
  </code></pre>
  
  <p>Push attempt:</p>
  
  <pre><code>user@none ~/rails_projects/project $ git push origin qa
  ERROR: The key you are authenticating with has been marked as read only.
  fatal: Could not read from remote repository.
  
  Please make sure you have the correct access rights
  and the repository exists.
  </code></pre>
  
  <p>Any idea how to fix this error?</p>