It is true that payday loans are illegal in Georgia. Great Sky Cash is not above the laws of the state. They are saying all that to you just to scare you so that you keep on making the payments. You will be liable for paying only the principal balance to them. As you've paid off the principal balance, you can ask for a refund of the excess amount that you've paid them. If they force you for further payments or do not refund the money, take legal actions against them.