Poor customer care service

I am up to date with my account payments. I twice deposited my instalments into the Truworths bank account but was surprised to get messages, emails and phone calls notifying me that my account is in arrears. I called the customer care thrice and a consultant gave me a WhatsApp number to send my proof of payment. It took them 2 days to respond to my message demanding my id number or account no. I immediately responded but nothing happened. I need my account to be updated as I am not in arrears and this is affecting my credit score. I am disappointed with their customer care service. It's slow and sloppy. Am not satisfied at all and will never want to carry on as their client.