Telkom not informing customers about changes to internet speeds and increases in prices

My internet speed has been incresed without notification from Telkom - from 20-50 megabytes. Customers on 10 megabytes were moved to 25 and customers on 20 were moved to 50 as the 10 and 25 are no longer available. Firstly, why have you done away with this and secondly, why did you not inform your customers, plus give them the option - I would have moved to 25, we don't need 50. To add insult to injury I can only cancel something I did not ask for in three months time. So for three months I am paying for something I do not need. Very angry!!!