Lexington law firm unsure

July 2013 my husband and I decied to try and clean up his credit.  We were told by lexington law firm they would help us clean his credit.  We would get full credit report and they would make disputes and remove the inaccurate charges.  After a month we had yet to receive the credit reports, or prof of any changes we called and asked to cancel this agreement.  We informed them in august of 2013 that we did not authorize any more charges.  We canceled the credit card and had a new card issued with a new number.  Lexington law got the new number and charged us $359.00 more over a 6 month period.  After we got a dispute filed with our credit card company they finally canceled our account,  We have given them 7 days to refund the 359.00 they have charged us.  They have our 359.00 we have nothing that proves anything was taken off his record.  they try and claim that we never spoke to them about cancelation.  I have phone records proving we spoke.  Any suggestions what we can do to get our money refunded.