I just noticed it. You're not the only person this has happened to. You'll need to buy the game at ATLEAST 9.09$ (current price after the 30% off). I'll start the refund process, but it does take 5-10 days to go through. Edit : Refund is done.
When you go to purchase, it's set to 9.09 by default, so unless you change it manually it shouldn't cause an issue. I've already refunded both amounts.
need help accidentally bought game twice well trying to dotation buy the game.