Lack of response, poor customer service

I don't usually do this, but I'm at my wits end with MBD, I was offered a special discount offer by MBD to settle my Woolworths account, grabbed the opportunity and the settlement amount was deducted via debit order on the 26th October 2023. Logged a call for a paid up letter on Monday,20th Nov and I was told there's a waiting period of 48hrs which was not an issue, I've been calling everyday since Wednesday, everyone keeps on telling me they are sending emails to Admin, a person by the name of Mathapelo was to respond to my email on Saturday,25th Nov, but till todate no response, even this morning of Monday, 27th November 2023, no one is willing to assist, what must a person do in order to get a paid up letter?