CellC - Disputed Debit

I received confirmation from CellC via SMS on 9 December regarding the cancellation of my contract. I was expecting the charge for the use of CellC from 1 December to 8 December which I was told would happen. Instead, I was debited with R79.01 on 24 December - I have requested FNB to REVERSE this amount. Feel free to contact me for payment for the 8 days, I KNOW that I am responsible for it.