Edgars Accounts Department Messing Up!

I am really unimpressed with Edgars' account management lately. Attaching interest to a 6 month interest free account (not to mention that they've now done away with that option after customers were told that our accounts would not change) - fine, I can deal with it. But now I receive phone calls and "friendly" SMSes reminding me to make payment by 01 Nov when I've already paid my account on the 24th Oct! I've had this account for 10 years and have never missed a payment. I want an updated statement reflecting my proper outstanding balance. Minus the added interest and minus my R600 payment for Oct.