Customer Support may ask you for your PayPal billing agreement ID or your order invoice ID when assisting you with a refund
Blizzard servers could not be reached or may be offline.
How to play Blizzard games in offline mode
More information about authenticator security codes
What to do when getting an error that the Battle.net Account has logged in somewhere else.
Some games require that you add a phone number to your Battle.net account
Instructions on linking your MLG and Blizzard accounts