Breach of contract

I cancelled my contract after the term came to an end- received confirmation my contract will be terminated from 28/10/2015. On 27/10/2015 received a sms confirming my contract has been converted to Easychat (payasyouGo). I still had minutes and data remaining on the account at that time. On 31/10/2015 the FINAL debit order went off. NOW, 01/12/2015 another debit order went off my account. This has not been authorized as our agreement was terminated as from 28/10/2015 and all obligations was met. I have been holding on the phone for your contact centre for more than 30 min. Send my complaint in email 1/12/2015, Again followed up 3 & 4/12/2015. Received a call 7/12/2015,(***). stating it will take 2 - 4 business days. Still no response and the issue still not resolved. HOW difficult can it be. All obligations related to the contract have been met by me , therefore the agreement and the inclusive authorization and obligations to Cell C should have been terminated as from 01/11/2015. GIVE ME MY MONEY BACK!!