MBD NOT PROVIDING A PAID UP LETTER

MBD gave me a discount on my standard bank debt. I paid the amount in November now Im struggling to get a letter stating that I have settle the account as per the discount amount given by the consultant. Everytime I call I'm being told that the matter has been escalated. I now get calls asking me when am I settling my account. I emailed the team leader Percy but hes no responding. I honestly don't know what to do anymore. Is there someone that can assist with the matter