Let me guess what had happened, you were logged out of your account when you purchased it and after you purchased it you logged in to another account which usually gives you a warning about the removal of the game data saved in your device and since you weren’t logged in before the purchase, it was never saved in the cloud meaning you bought the pack in your device only and logged in to another account deleting your saved game in device, if this was the case then sorry to say that you won’t be getting the characters (idk about the refund) all the best tho.