Call Center staff who are useless

I called today to get a settlement value and I was told that I cannot get it since the account is on my aunt's account which comes off my bank account. I have requested this settlement before and we have also sent a letter of authority since I have been paying for these cars since 2013 already. A settlement letter is related to payments which i am responsible for. Why does MFC think they can get money from my account and not provide me with details that i need to settle the account? And why are they sending me statements every month ? To top it off the Supervisor that I spoke to Simanani Makhaga does not even have answers to those questions and she is supposed to be leading a team.