Telkom Billing always in arrears

I had 2 products from Telkom. A fixed LTE contract, cellphone contracts ,Currently I have 1 product with Telkom. What I have noticed is Telkom is terrible when it comes to billing. An Invoice is generated and it will show you how much money is going to be deducted from you across the 2 product ranges. When the actual money is taken from your account. It will always not be correct. The Invoice system and the Billing system across product ranges does not work. You always are in arrears as they drop the money for 1 month. This has been continuing for over 3 years and SOE's have no interest in getting it right. This shows you the lack of accountability by internal audits and IT systems. I cannot be the only person having this issue. My fixed LTE has been cancelled for months , and they will never be able to recoup the money as their systems are flawed.