Get a bill refund.

I called an Xfinity and express to the customer service representative to NOT, i say again NOT mail me equipment, because i already picked mine up at a store. You guys sent it anyways disregarding everything i said and are now charging me with late equipment. What can i do to get this late fees off my payments. Xfinity cannot be sending me stuff i did not ask for and then charging me late return fees for. THIS HAS TO BE ILLEGAL.