RCS Account closure

Good day

I would like to express my unhapiness with RCS. I paid up their account on the 21 Feb 2020 for the amount I was owing. than in March they sent me a statement to say am owing the 69 for monthly service fee by which I paid R70 on 07 April 2020 and called them on the 09 April 2020 to close the account.

The consultant first told me that I have a balance of about R4 that was owing and I asked, what was that balance for as I had paid the account.She said the balance is the interest I then asked her how can they charge interest on a zero balance and she kept on insisting on that and asking her manager on the side and they eventually told me they were going to close the account, I asked them when because I wanted the account to be closed that day she said they cant close it that day because they need to allocate the money and they have processes that they follow.

I asked her what does that have to do with me because they could see the R70 I had paid by which she said they will close it within 36 days.

I told her I want that account closed and they must ensure that I am not billed for this month because I had paid that account.

Today I received a statement and they billed me on the 12th of April saying I owe R77.

So can they please close the account and reverse the charges because the reason I had called was to close the account by which they kept telling me stories and its clear that they were dragging this in order to bill me again.