Unprofessional and rude consultant

I am so annoyed by a consultant at Mr Price. Years back I had an account with MRP and I paid it up and closed it and 3 days ago I opp**** for an account and it was approved. Today this rude lady asks me about my old account that I used to have with MRP and claims that I didn't pay off the account. I managed to find the paid up letter, please resolve this issue.