title: how to fix Dialogflow agent won't restore from a zip file
body: <p>I am trying to restore my agent from an existing backup zip file but when I select the file to upload it, the file is selected but won't be upload and the window remain as it is without any error as you can see in the screenshot.
  I logged to my agent from a different computer and a different browser and still facing the same problem.</p>
  
  <p><img src="https://i.stack.imgur.com/1SRp2.png" alt="and this is a screenshot"></p>