Go to your bank or have them send you a copy of your acct listing any checks that have been cashed. See if that one has been cashed. If not, then I don't think they have a case and are using scare tactics to get you to pay more. If it has or hasn't, and they are still threatening you, take any and all data concerning the transaction to a lawyer and let him deal with it...I would also contact the better business bureau......Stir that turd they keep flauntin' at you.....In fact, you might want to contact them before getting an atty. Could be you wouldn't need one once they get wind of it.... Worth a shot..... If it's been cashed the bank statement would say how much it was, where it was cashed and who cashed it...