Worst bank ever - keep threatening me even after paying my credit card on time

I have a special arrangement agreement with FNB credit cards for R3216.72pm - agreement is dated 09/12/2022. I pay this amount as agreed every month, but I still receive an SMS and emails threatening me and saying that I didn't pay it. The amount on the SMS / email is also more than what was agreed. I have tried calling but their lines are forever cutting me off. When they call me and I answer the line also just cuts off as soon as I answer. And to send emails doesn't work as they also don't do anything to sort out the issues. My private banker is also of no use... The times that I did get through they said it was sorted out, but clearly it hasn't been updated and my payments hasn't been allocated as I've paid since the agreement in 2022. I have been battling to get this sorted since 2022!! This is the worst bank ever and I am disappointed in myself for changing to them from ABSA bank. Next step would be to go to Beeld because that is probably the only way to get this sorted out.