Unwilling to help on "late" payments

Over the past two months, I've had a constant fight with the accounts department from Game's Head Office. Over these two months I've been told that my account is overdue and I will be black listed. Due to unnecessary threats and disgusting behavior from the accountants, I eventually went into Game Fourways to sort out this issue. Game could not pick up that I had been paying my account for the past three month. After sending through the P.O.P's, they wouldn't/ couldn't "open the link". This has been going on every single week for 9 weeks. I then get a message this morning stating that Game has black listed me. Earlier today I asked to be put through to higher management and was told that no one can assist me. I run a business and having my name black listed isn't good on my record. I am disgusted by how this has been handled and if nothing is sorted out in the next week I will be taking this to my attorney. I now know that I will NEVER shop at Game again.