settlement letter

i had an account with Truworths that was handed over to MBD LC. i manage to pay my account in full 2017/03 and requested a paid up letter from mbd..up to this day i have not received any letter nor communication from them, each time i call iam being told that they will request the letter. I called in today and as usual they took my email address and said they will request it. i asked for the number where the letter must come from ********** 111 with no answer..MBD MY ACCOUNT IS BEEN SETTLED SEND ME THE SETTLEMENT LETTER AND STOP SENDING ME FROM PILLAR YO POST!!!!!!!I NEED IT URGENTLY.your prompt respond with regards to this will highly appreciated.