Notice of cancellation is a joke

Cancelling a contract - apparently notice need to be given 20 days / month in advance and NOT sooner - I phoned Vodacom to give notice of cancellation - It is 2 months prior to the cancellation date of which I am happy with.However they refuse to process the cancellation 'because it needs to be a month in advance' - In giving 2 months notice I exceed their expectations!!!! But this can't happen!!!!.I then decided to give written notice and send it via email to customer care - Unbelievable!!! They rep**** with a phone call saying they can't process my cancellation and that they are not the cancellations department.The most arrogant 'customer care' consultant that simply states nothing can be done AND THAT'S IT!!! On the other hand if you give one day late notice you will be liable for another months subscription fees - Vodacom let me guarantee you this !!! At a stage I had 5 different contracts with YOU and I WILL CANCEL EVERY ONE OF THEM!!!!!! when the time comes !!! - obviously never being a returning customer - I hope that every customer sees the arrogance in your business ways and do the same