Settlement amount/paid off account

Good Day My name is Emily Mashinini I have 2 RCS accounts, 1 Coricraft and 2 Normal RCS. Yesterday the 22 November 2020 Ive paid off my accounts because I want to close them and I went to Foschini Lakeside Mall to make a payment and when I go home I called RCS to ask them to close both my accounts. A lady then told me that she cant see my payments as yet I should call the next day which is today the 23 November 2020. When I call today I was told that they cant close my accounts because I only paid the balance not the settlement amount. And the interest on these accounts accumulate daily and currently they cant see how much are the interests accumulated so I must keep the account just to pay the interest since they will be formulated on the 12 of the next month. where on earth has anyone done that, to keep an account just to pay the interests? I had problems with these accounts that is why I do not need them anymore.