RCS
Charging interest on a closed account

I paid my RCS account on the 4th Mar 11, and on monday the 11th i sent an email to RCS to close my account and got a response from a Pumla saying the account will be closed but on the same day i went to the store to pay my outstanding balance of R0.86 but got the shock of my life that i need to pay R23.72 and when i called them to query this i was told that they cant do anything about this as this is interest on my account... what i dont understand is how can R0.86 generate interest of R22.86.

Company: RCS
Country: South Africa
City: Johannesburg

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