No customer care from Vodacom

I took out a 24 month data contract last year for R199. Only to find that my contract went up from April 2019. I went to Vodacom to question this, only to get told it's because of the VAT increase that now my contract went up, they would of sms'd with the information that the contract will increase. HELLO its a data contact in a pocket router, how am I meant to read the SMS. I was advised to phone customer care, I phoned them. They informed me that Vodacom had a price increase, first one in 10 years, I was told. How is it legal that they can increase my contract after I signed it for 24 months at a price of R199. So when I question if they can break the contract like that then I can beak the contract and cancel it. Only to be told no sorry if I cancel it I will need to pay. How can they just increase the price when they want to, but as a customer you need to stick to your contract. So disappointed in this, it will be the last time I ever have a contract with them.