Need to update the phone number on your Battle.net Account?
What to do when you receive the error "The phone number is invalid" when adding a phone number to your Battle.net account
Information about why you might get the message "An error has occurred." when you try to add a payment method
Troubleshooting steps for communication and transmission errors.
How to report a bug in StarCraft II
How to resolve this error when trying to log in to Battle.net
Information about this error when adding a phone number or a Battle.net Authenticator to a Battle.net account.
What to do if the website returns "Connection Error" when adding a phone number
How to create an account to play on the Public Test Realms