Contact them and ask them what the eff happened. If they don't reply in a timely manner or you don't like their reply and if they have a sales thread on the forum, so a reputation to keep, open a shitlist thread with your proofs, mods will look into it. If they don't have a sales thread, then you can open a PayPal dispute right away or do a chargeback with your credit card company, if you paid with a credit card.