Paying for useless service

I have been a Vodacom customer ever since I had a cell phone, I have been having contracts and everything had been good until now, the service is terrible. I am paying for data bundles for my laptop but this modem never connect to the internet, due to Vodacom network problem, and I am paying every month, paying for such a bad service, this is the same as being ******. After this contract of R347.51 I am paying per month, I would never use or recommend Vodacom to anyone, its a useless network. Sometimes my airtime could just disappear from my from without I using it up, when I phone, I get told that it might be that I was downloading something, when I tell them that I only get into facebook and whatsap from my phone, which is covered by BIS, I was then transferred to blackberry department and never obtained help, yet I still pay so much every month, what is this?, is it a ******* or what?