Small claims court

Hello, my business just got served with a small claims court suit for a balance owed at for some supplies purchased by an old employee. the balance is $4884.65 but with late fees and finance charges they are claiming a balance of $7249.16 plus court cost. My question is these charges are from May 2014, are they past the statute of limitations. The reason I ask is bc i tried calling and making settlement arrangements meaning I offered to pay full balance owed of actual charges asking them to waive late fees and they wouldnt work with us. So my second question is by law do we have to pay late fees and finance fees or just actual balance and being that these are 2 years late can we use the statute of limitations on our side?