VODACOM NOT REFUNDING MONEY FOR MORE THAN 8 MONTHS NOW!

I have been waiting for 8 months for vodacom to cancel a contract that ended and I didn't want to renew it. after phoning numerous times they eventually cancelled it, and was going to do my refund in five working days, I am again waiting for over a month now! I let my debit order bounce because it is less than the refund I am waiting for and this month they took all the money and still no refund!!!!! When my contracts are up, I will never use vodacom again!