Inefficient service from MBD

I was handed over to MBD attorneys for a Woolworths acc. I made a payment arrangement and made 1 payment and on the 2nd payment decided to settle the account. After more than 10 calls to MBD requesting a paid up letter I still have not received a letter and would like to put on record that Woolies choice of laywers is unprofessional and inefficient. My request is that i get my paid up letter from Woolworths as the account sits with them.