Leader's Merchant Services Charged me fees on a closed account! Internet

I received a statement in the mail that Leader's Merchant Services has charged me: minimum discount fees, regulartory fees, Additional fees and a security fee... all totaling $64.95 on an account that has been closed over a month. There has been no activity i.e. no transactions of any kind on this account in over a month and a half and they are still charging me fees. I filled out their "Cancellation Form" and faxed it TWICE to make sure they received it. Their is also a signal on my fax machine that says if a fax failed to go through and I did not get that signal from my fax machine.