Changing interest rate from 18 to 25

I recently downgraded my Credit Card as I was getting no sipport from my personal banker, being a Private Client.<br> <br> Guess what? He told me all the interest rates would stay the same.<br> <br> Did it? No. They changed my interest rate from 18 to 25.1 %<br> <br> Did I sign for this change?<br> <br> No - because their mail did not include a return address. The document is still with me.<br> <br> It seems FNB has totally lost track of client service.