Landlord forcing me to pay attorney fees?

My landlord has stopped cashing my checks even new ones. They are telling me I have to pay attorney fees for the rent demand they wrote me(in NYC you have to demand rent before starting a nonpayment summary proceeding): I was late paying rent but continued to make partial payments(my account is up to date now). I told them in NYC you need a judge to approve legal fees and they quit cashing my checks (because I refused to pay the legal fee. Any idea what their plan is?