Harassed client of Direct access in partnership with MBD

Good evening My Name is Nakho Xulu and i am being harassed by Direct access, debt collectors, MunnikBasson Dagama inc. In July 2024 I reached out to MBD and requested a settlement quote for my Direct access account, This is after numerous calls to the agency. They informed me on the Phone that the quotation was valid for only 14 Days. I informed them that i needed it o make a request from my employer so that I can settle the account. A lady by the name of Lesego Ngwenya sent me an email on the 19th of July 2024, confirming the settlement amount to be R16427.65. On the 30th of July 2024 I made payment to settle the account of R16427.65. I then sent through Proof of payment to the same lady and enquired what were the proceeding steps. I did not receive a response. I followed up again on the 19th of August 2024, still there was no communication from MBD, even the Phone calls stopped after I had settled the account. In April 2025 I started receiving phone calls again I informed them that the account had been settled but they continued to harass me. I then got in contact with another agent who advised me to email their manager Lesego M. *** <***>. I did send through an escalation but again there was no response from any manager at MBD. Today I am being sent demand letters and am still being harassed by these people, I have all these correspondence on email and have forwarded to Lesego M Who has continuously ignored me.

Please advise what recourse i must take now as they are threatening to take legal action against me.