Horrible service, extra charges, no statements, no help at all!!!

I have paid for three months and then I phoned in and asked for a statement. I clearly stated that I will not make further payment if I haven't received a statement. Then, I called again and spoke to someone who was quite helpful. The next day I got my statement. But now, MBD has charged me money, the same amount I have paid. I called in again today asking to speak to the same person, but the very very rude lady said that there is no way possible. The supervisor, very rude as well also said that I am not allowed to speak to the same person. Now, I do not know what the charges are for, how much interest they are asking and so on. How am I supposed to pay something, if I am clearly only paying the charges, and never the account. I have sent an email to MBD but still no response. I don't want to pay this account because I have no control or information on what is going on. This is not fair.