BofA Canada Bank

I has mbna master card and had credit %0 on balance transfer. I make all payments on timeIn Dec 2013, I made 1 purchase and pay it all in Feb 04. Then MBNA keeps charge financial fee (not interest fee) to my card, even I do not make any purchase, and payment all the payment due.They said this is financial charge not interest charge ! because my card is only for balance transfer not for purchase...there no thing like that in the contract[redacted]
Product_Or_Service: financial