Access facility doubled monthly payment

On August 25th, I made a payment of R8200 to my access facility account, and Capitec attempted to collect R8000 from my account for the month that I had paid for... I have never missed a payment, and if I am paid before my pay date, I always transfer the money to avoid problems, but to my disappointment, Capitec attempted to deduct even after I had made payment, and I noticed on the app that my monthly payment for the following month has increased despite the fact that the interest rate has decreased.... I am really frustrated.