Vodacom Increase Prices mid-contract?

When you take out 24 month contracts at Vodacom, you first review your monthly budget and decide if you could afford to pay the monthly fees. I have 2 contracts at Vodacom and a few months ago after Vodacom learnt they wont be able to take back data we've already paid for anymore they decided to increase the fees on my contracts by 22%.

A 22% increase in the monthly fees I pay not even halfway into the 24 month contract - short term gain for long term trust lost - whether it is legal or not is not the question. The question is more about ethics; I made a decision that I can afford the contract at a certain price and after I am locked in it becomes unaffordable. This is how Vodacom ****s a nation - I am sure everybody goes through the pain, some more than others.

I phoned the callcenter - they say its somewhere in the fineprint that they can hike prices at any stage and you can't get out of the contract without penalty even if you can't afford the new prices.