Bad service

Two months ago i upgrade my Vodacom accounts to take out new products. I been using the capitec linked payment method for some years now and i was never in arrears. I followed all the procedures and even paid the pro rata amount supp**** by them. by the first month after the upgrade problems started first sms saying iam going into arrears way before my scheduled pay date then sma it will affect your credit score i contacted vodacom and was told to send proof of payment to *** i recieved no feedback back for more then month and i paid the normal way on time. I call vodacom collection and resubmitted a POP and told the guy but i did this and who will take responsibility of my credit record that was no affected negatively by them he could not answer me i asked him to look at my account an see if i made payment for date in question only to find out i did make payment money was not allocated and i must call back in 5 hour to see if its up dated that is now two months later i when on credit my credit report and there appears now 1 month late on my name. Now who is to be blame and how can i fix this that was caused by Vodacom anyone please help