In 2009, Chase Bank sent me a letter saying that the fixed rate on my credit card was being raised from 3% to 9%. I contacted them and they gave me all sorts of incredible excuses for why and how they could legally do this to me.
The increase changed my monthly minimum payment from $115 to $380. I had been barely able to pay the $115, so a higher amount was out of the question.
I made call after call after call until I finally spoke to someone about arbitration. To make a long story short, it took about ten hours worth of phone calls, but we settled the matter through arbitration.
Chase closed my account, changed my interest rate to 0%, and put me on five year, fixed payment plan. I came out ahead for all the headaches.
Don't ever think that dealing with credit card companies guarantees that you'll come out on the losing end. With perseverance and by refusing to settle, you can get what you want.