Contract cancelling

Since the beginning of march i have been trying to cancel my contract with vodacom but instead of cancelling, Vodacom consultant suggested an upgrade for me and everything he said about the deal was nothing but a lie and i called again the next day to verify everything but i was so dissapointed because Vodacom is my one and only network;i trusted it so much but to be ****med like that and i had to cancel the upgrade which was successfully cancelled but my problem now is i have requested vodacom to cancel my contract because am unemployed but they refused to comply.now i can't even speak to their consultants due to high volume of calls i have made..so i don't know what to do anymore and i ended up stopping the debit order..