I dont want to upgrade, I want my contract to end on expiry dated.

I have received news that I can upgrade . ***. I don't want to upgrade I want to contract to end at expiry dated. Unfortunately Vodacom does not understand that and they are looking for al sort af excuses not to assist me in what to do and when the contract expire so that the contract can end. If you leave a comment on facebook, dont assist. If you leave more than 5 Comments they block you so that customers done see how you are handled