CELL C CANCELLATION OF CONTRACTS

I had two contracts with Cell C. I settled them off and I cancelled the contracts on the 2nd July 2019. Immediately after cancellation, I got smses confirming the cancellation and soon thereafter my benefits were taken away i.e. smses and minutes for both numbers. I called cell c this morning (3rd July 2019) enquiring if the account is fully paid up and asking if my benefits are taken away will I be liable to pay the full contract amount for this month and the agent told me that the person who closed my accounts was supposed to advise me that the benefit will be taken away and I will still be liable to pay the full contract amounts. I find it unfair. Firstly I paid R2199 and R3499 on the phones and they taken away all the benefits and they still expect me to pay another instalment for this month. If this happens I will migrate both my number and all my family number(5 of them) to Telkom. I will not take this from Cell C. They should not even deduct a cent from my account since my cellphones are now fully prepaid.