Shocking service as Vodacom simply ignored my cancellation request.

My mobile contract with Vodacom was due to expire in December last year. I had emailed Vodacom's cancellations department on the 29th of November to cancel my contract once it's term had expired to prevent it from becoming a rolling contract. Despite providing all the information I was told to provide, such as a letter confirming my desire to cancel the contract and a copy of my ID, I never heard back from the cancellations department and Vodacom has subsequently tried to debit my account for December and January. I'm currently studying in the UK and have no means to phone Vodacom directly, hence the email. Vodacom's failure to even acknowledge my request smacks of service of the worst kind. I still have a data contract with Vodacom, but I'm seriously thinking of simply cancelling it too and leaving Vodacom as a service provider. I've been a loyal customer of Vodacom's for well over a decade, but this just takes the cake. Service providers in the UK would never behave like this, which is galling considering that Vodacom is partly owned by Vodafone. I need to have my rolling contract cancelled as soon as possible and I'll think long and hard before recommending anybody to sign a mobile contract with Vodacom. I'm only available by email and this issue has seriously affected my finances and good name.