Bad service

I have a vodacom contract, it's still under 30 days and want to know, what legal right I have to cancel this contract because fed up is an understatement, I am extremely disappointed with their service, my data was blocked because of arrears while I have a debit order and the contract is only 20 days. I tried to contact customer but wow I had to explain my problem to a stupid bot not understanding a thing, I have heard people complaining about vodacom but decided to give them a benefit of the doubt, but joining them was the worst decision i ever made.