You will only get banned for reversing a payment if you reverse the payment and claim ‘fraudulent or unauthorized transaction’ as the reason. this forces funcom to assume you have been using an unauthorized payment source which results in a permanent ban.
If you use a service like paypal, you can reverse the charges by claiming you didnt get what you paid for (which you clearly didnt) and they will get you your refund without you getting banned.you shuold be able to do that with your credit card as well if you didnt use paypal.
Just a by the by, you should always use paypal when dealing with funcom if at all possible. Payments always go through and refunds arent an issue.
There is a common & misunderstood myth that any attempt to chargeback funcom will result in an automatic ban. This is not the case.
Just avoid using ‘fraud’ or ‘unauthorized transaction’ as the reason for the refund or chargeback and you wont have a problem.