Im still awaiting my refund!

In July 2015 i cancelled my cellphone contract and my last payment due was in August 2015. Vodacom debited my account in September again and i was told on the 29th September that the refund request has been sent to the finance department. It is now the 12th October 2015 and ive received no refund and no response.<br> <br> I cannot understand why hasnt my account been credited as yet?