title: Archive URL not found when trying to deploy using heroku buttons
body: <p>I am facing an error while trying to install an app using a heroku button (<a href="https://heroku.com/deploy?template=" rel="nofollow noreferrer">https://heroku.com/deploy?template=</a>"app_url").</p>
  
  <p><a href="https://i.stack.imgur.com/dggOK.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/dggOK.jpg" alt="enter image description here"></a></p>
  
  <p>This used to work all the time. Am I missing anything?</p>