BREACH OF CONTRACT AND POOR CUSTOMER SERVICE

I had an FNB Connect contract with FNB which was upgraded to unlimited . they were deducting R410.00 every month and I noticed that there was no deduction done today and I could not make calls either, at 12H50 I called them and I was informed that my contract was cancelled because I have exceeded my limits and it will take about 12 months for my contract to be reinstated. I was so amazed because 1. I was not informed about this condition 2. there was no notification or communication done to me about this 3. I was upgraded to unlimited and my monthly subscription was increased.\ FNB is in morror as they acted out of good faith. They are in total breach of the contract or agreement. I want the contract to be reinstated to no less favourable terms than those that existed prior their unilateral decision to terminate the contract.