Poor service

I have had a contract with Vodacom for many years. Last year (2017) I renewed my contract. All was fine until about April this year, when my account suddenly started going up each month - not related to the VAT increase. The first time I inquired about this, the operator said that it would all be sorted out. It wasn't. These are my complaints: 1. My contracted amount was increased by about R30 per month without any warning. As it IS a contract, I don't see how they can do this. 2. At the end of May, 100 minutes disappeared overnight. I paid for this: therefore that is theft. 3. In June I have been billed over R90 for a service which appears to have something to do with games. As I am a pensioner and have NEVER used my phone for games, this is a totally unacceptable situation. When I phoned the call centre the person at Vodacom "unsubscribed" me: but obviously I will still have to pay the R90-odd that was billed. How can Vodacom allow this to happen? It was done without my knowledge and Vodacom seems to simply allow such things.