Useless service

I have a problem with the services of MBD, they very useless. I had an FNB Personal loan account which was handed over to them last year and a consultant by the name of FaithK called me and told me I have a discount on the account and had to pay R350 to close the account. I paid the amount last year July 2019 for R350, till now I have been waiting for a Paid up letter but no luck. Now to my surprise I receive an sms this morning to pay R18.49 immediately, I called back the number on the sms and was attended by a consultant by the name of Aziza who refused to give me her surname. I mean as a customer I have the right to know who I am dealing with just to be sure if the call is not a **** because at this point I feel like MBD are ******** people off their money. I wrote a review 2 month back regarding the issue and no one from MBD bothered to call me back. And now Aziza refuses to give me her surname even though I explained to her that I need to be sure that I am speaking to a consultant from MBD, but she just said no she cannot give me her surname. How do you refuse to give me your surname meanwhile you have all my details. Honestly MBD are just ******** people of their money.