Paid up letter request which has not been granted

I had an account that was handed over to TFI Attorneys by BASH, the account has been recently settled in June last month. When I called for a paid up letter I was told I will get it in the next three months, I advised them I know the whole process of settling an account and issuing a client with the paid up letter, they went on to say they are doing this in case I decide to reverse previous debit orders that has gone off months ago. The service when I have settled the account is horrible, very pathetic they are the worst. I am still waiting for the paid up letter until now I have reached out many times they just give me lame responses.