If your account has been stolen, you should first check your account and computer security to verify your authenticator registration and security status.

Information about reporting BattleTags in Hearthstone

Information on error BLZBNTBGS00000026

How to report spam, offensive language, names, or BattleTags in Diablo II: Resurrected

What to do when friend requests are not working

What to do if both players show as their class without a name.

Troubleshooting for adding BattleTag or Real ID friends.

What to do if a mistake was made with a purchased gift

Information on error BLZBNTBGS80000020

Troubleshooting for issues loading the BattleTag or Real ID friend list