Customers have more power than companies would like you to believe. Politely explain the situation to customer support, and ask for a refund. If they refuse, mention that you purchased a game that was promised to work for at least several months, and you haven’t received the product you paid for. Because of that, you’re considering charging back through your bank. If that doesn’t work, say you’ll charge back if they don’t refund. If that doesn’t work, actually charge back through your bank. Banks are surprisingly cool about it as long as you don’t do it too often. Of course, you need to buy the game directly (no account balance) from a credit card.

Just don’t be a jerk to the support person, because it’s almost certainly not their fault. It’s also less likely to get you what you want. They’d rather give you what you want so you go away, and you just need to give them reasons that they can relay to their supervisor if necessary.