Double charge of trailers

We would like to settle our account, but they debited us on 2 different accounts - One is ours and another one they just created. They are in possession of our vehicle registration numbers which we pay on our account. Our trailers also seems to be being charged as well. We handed trailer registration papers in at their office in Centurion. Our account is nowhere in arrears. Why debit us on the hidden account? They refuse to investigate and delete this hidden agenda of theirs.<br> Up till now Centurion tells us they would send us the 60% discount invoice, but nothing happens and they keep on debiting us.<br>