I have just received a demand letter from a debt collection agency for a sum of 240Eu,I believe there is no debt as I had paid it off last year on time,I am waiting for the bank to produce the cheque but the original company say they have no record of it.I am concerned that while I am trying to sort this out that it could effect my credit rating.Is this the case?any comments much appreciated,needless to say I am really p***** at the original company.