Lazy and rude employee

I've just had the worst service from Rosemary Jakavula. She was rude, refused to listen, impatient and utterly disinterested to solve my issue. I has a Queenspark account that I closed March 2020 but a year later, I started getting calls from MBD attorneys saying that I have been handed over. Rosemary said I should get a paid up letter from MBD but I've never paid anything to MBD. She puts me on hold and comes back and says that I need to call MBD since I've finished paying them and get a paid up letter. I HAVE NEVER PAID ANYTHING TO MBD!!!! The more i tell her that I have nothing to do with MBD, the more she tells me go to MBD. I closed my account with Queenspark, their consultant neglected to close my account on their system, the account continued to attract monthly fees and interest, hence the handing over. Now this debt has been sold to MBD and they are harassing me multiple times a day. Get my name off MBD's books. NOW!!!! And have someone call me to sort this out ASAP.