"There's nothing we can do" -VODACOM

So I upgraded my data contract effective end of February 2019 and I was told it would cost me R199 per month. Now in April I get a statement and invoice for R212. I called vodacom customer care and they sent me to the accounts department who sent me back to customer care. The story is there was an increase and pricing and this was not communicated to me (I provided evidence of this). The lady then tells me there's nothing she can do because "they sent out communication" to all customers even though I told her I received nothing and that is why I am surprised at the amount and calling them 2 months into my contract. She refused to take my matter seriously or even recommend an remedial action.

Vodacom, is this how you treat your customers? change things without notification and not take responsibility for anything because "there's nothing you can do?" If this is how I, as a customer for more than 2 years with you am treated, I would like to cancel and take my business where I will be cared for and my complaints will matter. This is really no way to treat a customer!