trying to terminate a contract

Good day. I turn to HelloPeter in the hope that I can finally get a response from Vodacom. I have moved overseas and have a 24 month data contract with Vodacom that expires at the end of March 2016. I have sent no less that 3 email to the contact centre advising them that I wish to cancel the contract and that they need to confirm receipt and cancellation in writing. I have not had a single response. The reference was 001C8aBC6RVK6WYF and I even escalated it ECLO. Nothing. No interest. So again: I hereby wish to give notice of termination of the data contract at the end of March 2016. Cell number linked to this data contract is ***; account number I***. Note this is a data contract, it is in a modem, not a phone, I want confirmation sent to my email not to my phone (so that I can have record thereof). So please people, if you have any self respect confirm cancellation in writing. I don't really care that you are *********** and incapable of customer service, just confirm cancellation.