Going to hijack my top comment here to post an addendum - Do [u]NOT[/u] process a chargeback with your card carrier to get a refund. Going this route may result in your battle.net account being banned. Instead follow the posted guide if you purchased through battle.net or the Blizzard app - or if you purchased through another retailer follow up with them about a refund.
I could care less at this point. Blizzard refused to give me a refund because I kept retarting my computer and trying to play for over 3 hours.