title: update creative in existing ad group
body: <p>We are trying to update\replace the creative of existing adgroup with no success.
  According to the documentation is supported:
  Updating and deleting ad groups</p>
  
  <p>*<strong>Using the ad group ID, you can update the following fields in an ad group:
  name
  max_bid
  adgroup_status
  bid_type
  targeting
  creative*</strong></p>
  
  <p>We pass a new creative id to the adgroup using the graph api , but nothing happens.</p>
  
  <p>How can we update the creative of an existing adgroup?</p>
  
  <p>Found a solution, you can replace the creative but you can't edit an existing creative.</p>