How to report another player that is using an offensive or inappropriate BattleTag
How to report a player who is threatening with harming another person or a place
How to block communication from another player in the Battle.net Desktop App.
How to report harassment taking place within Battle.net chat (mobile or desktop)
Reporting your own behavior won't prevent action.
How to submit feedback or report an issue with the matchmaking system
What to do if you think another person or group of people has targeted a DDoS attack on you