Cancellation of contract

My Virgin Mobile contract expired on the 5th of November, and I contacted Virgin Mobile on the 5th of October re my upgrade. They offered me an upgrade, but when they did credit vetting, I did not qualify for the wonderful new contract, instead, I qualify for a topup contract of approximately R500 a month (this is R200 more than my current contract). I decided to cancel with Virgin, and did so via email to mr. Sebone Mashigo (the very nice person that phoned me regarding my upgrade). He rep**** (I am copying and pasting his email): <br> \Please contact *** from your Virgin number or any number to cancel the contract due to security purposes that the call should be recording upon an interaction pertaining the Cancellation."(21 October)<br> NO REFERENCE TO A DATE FOR CANCELLATION! I phoned them this morning as I have been working in the district"