household finance rip off

i have a revolving credit line with hfc. i was just informed that the amt i pay every month, the only amt that goes to the principle is 24.00 out of 331.00 a month. i called them and they even said that the payoff was more than the balance. it seems like the more i pay the more the balance goes up. when i asked them to drop my interest rate they said that they were not taking any applications. this to me seems like a rip off