No error message nothing.
HELP I WANNA GIVE YOU MONEY BLIZZ
08/16/2013 11:23 PMPosted by ArcagnionWe are aware of an issue where some players receiving an invitation to the Hearthstone beta are unable to make purchases from the Hearthstone in-game store. This particular error does not imply a problem with your payment method or credentials, and instead is due to a technicality related to where you Battle.net account was originally created. You do not need to change anything related to your account or settings. The development team is currently working on a fix and we’ll post an update here once the issue is resolved.
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