code: public ChangesetInfo unsubscribe(long id)
  	{
  		SingleElementHandler<ChangesetInfo> handler = new SingleElementHandler<>();
  		ChangesetInfo result;
  
  		try
  		{
  			String apiCall = CHANGESET + "/" + id + "/unsubscribe";
  			osm.makeAuthenticatedRequest(apiCall, "POST", new ChangesetParser(handler));
  			result = handler.get();
  		}
  		catch(OsmNotFoundException e)
  		{
  		/* the API is inconsistent here when compared to the "subscribe" command: It returns a 404
  		   if the changeset does not exist OR if the user did not subscribe to the changeset. We
  		   want to rethrow it only if the changeset really does not exist
  
  		   TODO monitor https://github.com/openstreetmap/openstreetmap-website/issues/1199
  		   */
  			result = get(id);
  			if(result == null) throw e;
  		}
  
  		return result;
  	}
docs: Unsubscribe the user from a changeset discussion. The changeset must be closed already.
  
  @param id id of the changeset
  @return the changeset
  
  @throws OsmAuthorizationException if this application is not authorized to modify the map
  (Permission.MODIFY_MAP)
  @throws OsmNotFoundException if the given changeset does not exist