Disgusted to the core!!!

Please fix your billing issues. This is sickening to the core I cannot do this with you any longer if you are sick of having clients please kindly our contract and let us move on to a much more competent service provider. The initial fibre contract is R655.00 I made a total payment of R1020.00 on the 23rd of October. How is it that we have an outstanding amount of R428.00 on a router that was taken out on the 8th but was only received on the 17th of October. I'm am disgustingly unhappy with the service I have received with you where billing is concerned. I previously paid twice in one month to avoid having to deal with this nonsense. But here we are again. What upsets me further you actually received the payment and the next was to be generated on the 1st/3rd of November to be payable by 30th November. Tell me how are we in arrears by R428.00 if you can't do that please come collect the last router... make sure it is before the 7th as the national credit regulatory allows for a cooling period of 30days.... your billing method is very flawed. In fact it is down right stupid. This is infuriating. What worse I paid as per the invoice received on the 22th of November. How in God earth do I owe you R428.00