Complain

I am not happy with vodacom . Few months ago an indian lady from vodacom called me that they can reduce my instalment for my current contract for me to pay a bit lesser and i agreed , Boom at the end of the month my premium has increased with almost R 900.00.I have been in contact with vodacom to cancel the migration and my installmnet to go[ back to its amou but no they continue with the crazy premium not helping me .What type of service is that and i also pay my monthly premium per but but being treated like **** ,I AM NOT HAPPOY AT ALL WITH VODACOM