Very poor service on billing with no communication

I was sold a modem in April and the first installment was taken off then all of a sudden the next debit did not come off, when I called telkom I found out that the banking details were incorrect. This after u already took the first installment.<br> I change the banking details and still no money has come off. I then did a electronic payment last month. Today I was called by your debt company and advised my account is in arrears and that I have been handed over. This is really poor service that has left a very bad taste in my mouth.<br> <br> Please can some contact me and explain what is happening with my account. I would also like to cancel this contract with immediate effect as I can not continue to chase after telkom.<br> Please let me know where I can send the device