Shocking Payment Rejection Fees

After our payment was rejected, we were charged a payment rejection fee nearly 3x the balance due. We understand an outstanding balance needs to be paid but to add interest and such a shocking penalty fee, is not a fair practice. Within two months our invoice went from R78 to R504.32 - for a service we do not even use. With lockdown, there was a delay with post and we only received invoices for June & July 2020 now. Although the consultant online was friendly, Telkom was not willing to help us.