Premium increase

These guys increased my premium without notifying me I have been paying R399.00 and they sent me a message saying I need to pay R481.25 to stay connected, my question was why is that? The service consultant told me the premiums has gone up. Why did I not receive any communication about the premium increase of which I didn't know. And I was told the supervisor will contact me up to now I have not received any call or email yet they do have all my contact details. I want them to tell me why was I never contacted with regards to the increase and they want to tell me to pay. He'll no I'd rather cancel the subscription. Why was I never notified of the changes