MTN ARE *******!!!!!!!!!!!!

At the end of April 2018 I went into the MTN Westgate store to enquire about my two contracts at MTN and their expiry dates. I was informed that my contract for number ********** 687 expires on 24/7/2018. They also advised me that I must give 30 days notice prior to 24/7/2018 in order for MTN to then close the contract. On 25/6/2018 I contacted MTN to give the 30 days notice - REFERENCE NUMBER: ********** 48. On 20/07/2018 I was debited with R1068.60 (R434.60 MORE THAN MY USUAL MONTHLY AMOUNT!!!!!) When I enquired with MTN on Monday I was told that it is because I terminated my contract. THE CONTRACT IS EXPIRING!!!!!!!!!!!!!!! HOW CAN YOU CHARGE ME FOR SOMETHING THAT IS EXPIRING?????????????????? OR IS THIS YOUR WAY OF PUNISHING YOUR CLIENTS IF THEY DO NOT RENEW THEIR CONTRACTS WITH YOU AFTER EXPIRY????????????????????? I WANT THIS REVERSED IMMEDIATELY!!!! IF NO CREDIT TO MY ACCOUNT BY 1 AUGUST 2018, I WILL LOG THIS INCIDENT WITH THE OMBUDSMAN.