Bank of America Credit Card Complaint

Bank of America Credit card department,

APR or interest rate Maryland

-/-/-, I 've noticed that even though I have been paying more than my minimum payment amount and paying it on time, my balance was slow to go down. When I checked my account, I noticed that my fixed interest rate of 10.99 % ( since -/-/- ) was moved to an interest rate of 11.15 % variable. I called Bank of America to ask why my interest rate was switched from a fixed to a variable when I have never not paid my bill, always paid more than the minimum amount and always paid on the due date, Bank of America told me they just did it to me. I asked them was n't that against the law, especially since they never even notified me of hiking up my rate? They apologized and acknowledged that they never notified me and will now send out something to me in the mail. Is this legal? Can they get away with stealing my money like this? I need help in resolving this. Bank of America can not just switch my fixed APR from 10.99 % to a variable, when I did nothing wrong.