2 WEEKS TO ALLOCATE ACCOUNT PAYMENT!!!!

On the 29th of September I paid my account but accidentally put the incorrect last 2 digits on my reference number when making the payment, on Saturday the 3rd October I phoned the call centre to alert them of this and have my payment reallocated after numerous phone calls and emailing proof of my payment 3 times I'm beyond annoyed now, its been over 2 weeks now that I brought the matter to their attention have been trying to get it sorted out and Im still getting sms's to say my account is in arrears! This is quite frankly shocking customer service I made the same mistake with my Woolworths payment and it was sorted out in a day! I've had an account with RCS for 4 years and never once missed a payment! Serioulsy this has to be sorted out now surely for such a huge company you cant have such an *********** finance team!