Extension of contract without consent

I have been trying to sort this out 4 months now and surprisingly no one at telkom mobile can help me. I signed a contract to my phone upgrade in January 2016 and my old phone contract was served to expire in March 2016. But Telkom mobile billed me for both phones in January, February and March. So in actual fact my new contract started in January and not in March according to their system. Which means I'm paying an extended contract if 26 months and not the 24 I signed up for. This is ******* and I'm protected under consumer protection act which actually does acknowledge this as an ******* activities on behalf of telkom mobile. I have tried to sort this out with telkom but no one seems to have the authority to assist me and neither can they point me to someone who can. So this is my next step before I start laying complaints and also expose them in the newspaper. This is just wrong