Upgrade not resolved

I entered into a Uchoose flexi contract with vodacom in 2015, and at the same time with Mtn. I upgraded my mtn contract july 2017 as i was supposed to but when i wanted to upgrade vodacom they said the contract only expires in march 2018. That is clearly longer than 24months. We have made numerous calls to customer care and everytime they say they can see there is a problem with my contract as i should have upgraded months ago. This has caused untold amount of minutes on the phone with these people and ni resolution is found. My statement even shows a neg balance (meaning we have paid far more than we should) of R1900. But still they are deducting money off that neg balance every month. So now rhey are even *****ing my money. In beginning of dec we phoned again and Call centre lady said she sees our contract expired in june 2017 and we should have upgraded but the system still shows march. She then logged a complaint with head office (1- ********** ********** ) we got a msg it has been resolved but when we phoned again today they are still waiting for the contract!!!! This is ridiculous and if this is the service we can expect of a national company i dont want any part of it. They are in breach of contract and taking their sweet time fixing it. This issue has been unresolved for more than 5 months now. How much longer must i wait!!!!!i am severly tempted to go to the Consumers Complaints Commission and report Vodacom for this. I want this resolved asap, as this phone isnt even more operational!!! Very disgusted and highly de moer in with their service.