Disappointed and angry

I am an African Bank customer, customer number is ***. The total amount owed was R52 000. I was expected to pay off or settle the very long outstanding amounting to R2500 in July 2023. African Bank decided not to debit the outstanding settlement amount of R2500. I have been trying to contact them by phone and email but to no avail. Now my credit profile is in a mess because of them. I am very disappointed since I have been looking forward to end business with them. I am always being told to visit the branch which never happened when I have been paying them. Please help me to get in touch with them. Thank you.