Price increase on contract

I've received a communication from Vodacom that my Smart S subscription will increase from R199 to R209 per month. I have signed a 2-year contract which makes this increase an infringement of my consumer rights and effectively *******. I see there are other complaints on Hello Peter regarding the same issue with no response from Vodacom. I have also sent an email enquiry directly to Vodacom. I will be awaiting a response. If not, I intend to take this issue further and contact Consumer Protection.