#1

The documentation for PUT request on Targeting Criteria needs to be updated. (Link- Targeting Criteria | Docs | Twitter Developer Platform)

I found out that for campaign_engagement field you can pass in comma separated camapign_ids
eg: https://ads-api.twitter.com/0/accounts/hkk5/targeting_criteria?line_item_id=6zva&engagement_type=ENGAGEMENT&campaign_engagement=abc,xyz

#2

Sorry about that, and thanks for clarifying. We’ll work to update it!